II880TA-02.pdf

Installation, Start–Up, Operating and

Service and Maintenance Instructions

NOTE: Read the entire instruction manual before starting the

installation.

TABLE OF CONTENTS

SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

LOCATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Table 1 – Minimum Free Area Required for Each Combustion Air

opening of Duct to Outdoors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Table 2 – Minimum Space Volumes for 100% Combustion, Ventila-

tion, and Dilution from Indoors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Table 3 – Opening Dimensions - In. (mm). . . . . . . . . . . . . . . . . . . . 10

AIR DUCTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

GAS PIPING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Table 4 – Maximum Capacity of Pipe . . . . . . . . . . . . . . . . . . . . . . . 14

ELECTRICAL CONNECTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Table 5 – Electrical Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

VENTING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Table 6 – Minimum Allowable Input Rating of

Space-Heating Appliance in Thousands of Btuh per Hour. . . . . . . . 22

Table 7 – Combined Appliance Maximum Input Rating

in Thousands of Btuh per Hour. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Table 8 – Recommended Minimum Vent Height Per Furnace and Vent

Orientation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

START-UP, ADJUSTMENT, AND SAFETY CHECK . . . . . . . . . . . 26

Table 9 – Altitude Derate Multiplier for U.S.A.. . . . . . . . . . . . . . . . 27

Table 10 – Gas Rate (CU ft./hr) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Table 11 – Blower Off Delay Setup Switch . . . . . . . . . . . . . . . . . . . 29

Table 12 – Cooling Airflow Adjustments from 1.5 to 6 Tons . . . . . 30

Table 13 – Air Delivery - CFM (With Filter). . . . . . . . . . . . . . . . . . 31

Table 14 – Furnace Setup Switch Description . . . . . . . . . . . . . . . . . 35

Table 15 – Orifice Size and Manifold Pressure (In. W.C.) for Gas Input

Rate (Tabulated Data Based on 22,000 Btuh High-Heat/14,500 Btuh

for Low-Heat per Burner, Derated 4 Percent for Each 1000 Ft. (305 M)

Above Sea Level) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Table 16 – Orifice Size and Manifold Pressure (In. W.C.) for Gas Input

Rate (Tabulated Data Based on 21,000 Btuh High-Heat/14,500 Btuh

for Low-Heat Per Burner, Derated 4 Percent for Each 1000 Ft. (305 M)

Above Sea level). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

SERVICE AND MAINTENANCE PROCEDURES. . . . . . . . . . . . . . 38

Table 17 – Filter Size Information - In. (mm) . . . . . . . . . . . . . . . . . 40

SEQUENCE OF OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

WIRING DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

TROUBLESHOOTING GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

PARTS REPLACEMENT INFORMATION GUIDE . . . . . . . . . . . . . 50

EXAMPLE OF MODEL NUMBER . . . . . . . . . . . . . . . . . . . . . . . . . 50

TRAINING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Most states in the USA an jurisdictions in Canada have laws that require

the use of Carbon Monoxide (CO) alarms with fuel burning products.

Examples of fuel burning products are furnaces, boilers, space heaters,

generators, water heaters, stoves/ranges, clothes dryers, fireplaces,

incinerators, automobiles, and other internal combustion engines. Even

if there are no laws in your jurisdiction requiring a CO Alarm, it’s highly

recommended that whenever any fuel burning product is used in or

around the home or business that the dwelling be equipped with a CO

Alarm(s). The Consumer Product Safety Commission recommends the

use of CO Alarm(s). The CO Alarm(s) must be installed, operated, and

maintained according to the CO Alarm manufacturer’s instructions. For

more information about Carbon Monoxide, local laws, or to purchase a

CO Alarm online, please visit the following website.

https://www.kidde.com.

A200103

Portions of the text and tables are reprinted from NFPA 54/ANSI Z223.1E, with permission of National Fire Protection Association, Quincy, MA

02269 and American Gas Association, Washington DC 20001. This reprinted material is not the complete and official position of the NFPA or ANSI

on the referenced subject, which is represented only by the standard in its entirety.

880TA/881TA

80% AFUE, Two-Stage, Variable–Speed

4–Way Multipoise, Non-Condensing Gas Furnace

Series A

WARNING

CARBON MONOXIDE POISONING HAZARD

Failure to follow this warning could result in personal injury and/or

death.

Carbon Monoxide (CO) is a colorless, odorless, and tasteless poisonous

gas that can be fatal when inhaled. Follow all installation, maintenance,

and service instructions. See additional information below regarding

the installation of a CO Alarm.

Use of the AHRI Certified TM Mark indicates

a manufacturer’s participation in the program.

For verification of certification for individual

products, go to www.ahridirectory.org .

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

A190045

Fig. 1 – Dimensional Drawing

FURNACE SIZE

CABINET WIDTH

OUTLET WIDTH

TOP AND

BOTTOM FLUE

COLLAR

BOTTOM

INLET WIDTH

VENT

CONNECTION

SIZE

SHIP WT.

LB (KG)

36045C17 17-1/2 (445) 15-7/8 (403) 11-9/16 (294) 16 (406) 4 (102) 118 (53.5)

36070C14 14-3/16 (360) 12-9/16 (319) 9-5/16 (237) 12-11/16 (322) 4 (102) 118 (53.5)

48070C17 17-1/2 (445) 15-7/8 (403) 11-9/16 (294) 16 (406) 4 (102) 126 (57.1)

60070C21 21 (533) 19-3/8 (492) 13-5/16 (338) 19-1/2 (495) 4 (102) 147 (66.7)

48090C17 17-1/2 (445) 15-7/8 (403) 11-9/16 (294) 16 (406) 4 (102) 134 (60.8)

60090C21 21 (533) 19-3/8 (492) 13-5/16 (338) 19-1/2 (495) 4 (102) 153 (69.4)

60110C21 21 (533) 19-3/8 (492) 13-5/16 (338) 19-1/2 (495) 4 (102) 156 (70.7)

66135C24 24-1/2 (622) 22-7/8 (581) 15-1/16 (383) 23 (584)

4 (102)

*. 135 size furnace require a 5 or 6-in. (127 or 152 mm) vent. Use a vent adapter between furnace and vent stack. See Installation Instructions for complete installation

requirements.

169 (76.6)

U.S. ECCN: Not Subject to Regulation (N.S.R.)

SD5523-4 REV. B

NOTE: ALL DIMENSIONS IN INCH (MM)

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

SAFETY CONSIDERATIONS

Installing and servicing heating equipment can be hazardous due to gas

and electrical components. Only trained and qualified personnel should

install, repair, or service heating equipment. Untrained personnel can

perform basic maintenance functions such as cleaning and replacing air

filters. All other operations must be performed by trained service

personnel. When working on heating equipment, observe precautions in

literature, on tags, and on labels attached to or shipped with furnace and

other safety precautions that may apply.

These instructions cover minimum requirements and conform to existing

national standards and safety codes. In some instances, these instructions

exceed certain local codes and ordinances, especially those that may not

have kept up with changing residential construction practices. We

require these instructions as a minimum for a safe installation.

Wear safety glasses, protective clothing and work gloves. Have fire

extinguisher available during start-up and adjustment procedures and

service calls.

This is the safety-alert symbol . When you see this symbol on the

furnace and in instructions or manuals, be alert to the potential for

personal injury.

Understand the signal words DANGER, WARNING, and CAUTION.

These words are used with the safety-alert symbol. DANGER identifies

the most serious hazards which will result in severe personal injury or

death. WARNING signifies a hazard which could result in personal

injury or death. CAUTION is used to identify hazards which may result

in minor personal injury or product and property damage. NOTE is used

to highlight suggestions which will result in enhanced installation,

reliability, or operation.

The following additional safety considerations should be followed for

gas furnaces:

1. Use only with type of gas approved for this furnace. Refer to the

furnace rating plate.

2. Install this furnace only in a location and position as specified in the

“Location” section of these instructions.

3. Provide adequate combustion and ventilation air to the furnace

space as specified in “Air for Combustion and Ventilation” section.

4. Combustion products must be discharged outdoors. Connect this

furnace to an approved vent system only, as specified in the

“Venting” section of these instructions.

5. Never test for gas leaks with an open flame. Use a commercially

available soap solution made specifically for the detection of leaks

to check all connections, as specified in the “Gas Piping” section.

6. Always install furnace to operate within the furnace’s intended

temperature-rise range with a duct system which has an external

static pressure within the allowable range, as specified in the

“Start-Up, Adjustments, and Safety Check” section. See furnace

rating plate.

7. When a furnace is installed so that supply ducts carry air circulated

by the furnace to areas outside the space containing the furnace, the

return air shall also be handled by duct(s) sealed to the furnace

casing and terminating outside the space containing the furnace.

See “Air Ducts” section.

8. A gas-fired furnace for installation in a residential garage must be

installed as specified in the warning box in the “Location” section.

9. The furnace may be used for construction heat provided that the

furnace installation and operation complies with the first

CAUTION in the LOCATION section of these instructions.

10. These Multipoise Gas-Fired Furnaces are CSA (formerly A.G.A.

and C.G.A.) design-certified for use with natural and propane gases

(see furnace rating plate) and for installation in alcoves, attics,

basements, closets, utility rooms, crawlspaces, and garages. The

furnace is factory-shipped for use with natural gas. A CSA (A.G.A.

and C.G.A.) listed accessory gas conversion kit is required to

convert furnace for use with propane gas.

11. See Fig. 2 for required clearances to combustible construction.

12. Maintain a 1-in. (25 mm) clearance from combustible materials to

supply air ductwork for a distance of 36 in. (914 mm) horizontally

from the furnace. See NFPA 90B or local code for further

requirements.

13. These furnaces SHALL NOT be installed directly on carpeting, tile,

or any other combustible material other than wood flooring. In

downflow installations, factory accessory floor base MUST be used

when installed on combustible materials and wood flooring. Special

base is not required when this furnace is installed on manufacturer’s

Coil Assembly Part No. CNRV, CNPV, CAP, or CAR or when Coil

Box Part No. KCAKC is used. See Fig. 2 for clearance to

combustible construction information.

WARNING

FIRE, EXPLOSION, ELECTRICAL SHOCK, AND

CARBON MONOXIDE POISONING HAZARD

Failure to follow this warning could result in dangerous operation,

personal injury, death, or property damage.

Improper installation, adjustment, alteration, service, maintenance, or

use can cause carbon monoxide poisoning, explosion, fire, electrical

shock, or other conditions which may cause personal injury or property

damage. Consult a qualified service agency, local gas supplier, or your

distributor or branch for information or assistance. The qualified

service agency must use only factory-authorized and listed kits or

accessories when modifying this product.

CAUTION

FURNACE RELIABILITY HAZARD

Failure to follow this caution may result in unit component damage.

Application of this furnace should be indoors with special attention

given to vent sizing and material, gas input rate, air temperature rise,

unit leveling, and unit sizing.

CAUTION

CUT HAZARD

Failure to follow this caution may result in personal injury.

Sheet metal parts may have sharp edges or burrs. Use care and wear

appropriate protective clothing, safety glasses and gloves when

handling parts, and servicing furnaces.

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

INTRODUCTION

A10269

Fig. 2 – Clearances to Combustibles

The 4-way multipoise Category I fan-assisted furnace is CSA (formerly

A.G.A. and C.G.A.) design-certified. A Category I fan-assisted furnace is

an appliance equipped with an integral mechanical means to either draw

or force products of combustion through the combustion chamber and/or

heat exchanger. The furnace is factory-shipped for use with natural gas.

This furnace is not approved for installation in mobile homes,

recreational vehicles, or outdoors.

This furnace is designed for minimum continuous return-air temperature

of 60°F (15°C) db or intermittent operation down to 55°F (13°C)db such

as when used with a night setback thermostat. Return-air temperature

must not exceed 80°F (27°C) db. Failure to follow these return-air

temperature limits may affect reliability of heat exchangers, motors, and

controls, see Fig. 3.

For accessory installation details, refer to the applicable instruction

literature.

NOTE: Remove all shipping brackets and materials before operating the

furnace.

A06745

Fig. 3 – Return Air Temperature

A02054

Fig. 4 – Prohibit Installation on Back

A93044

Fig. 5 – Installation in a Garage

CODES AND STANDARDS

Follow all national and local codes and standards in addition to these

instructions. The installation must comply with regulations of the

serving gas supplier, local building, heating, plumbing, and other codes.

In absence of local codes, the installation must comply with the national

codes listed below and all authorities having jurisdiction.

In the United States, follow all codes and standards for the following:

Safety

NFPA 54/ANSI Z223.1 and the Installation Standards, Warm Air

Heating and Air Conditioning Systems ANSI/NFPA 90B.

General Installation

Current edition of the NFGC and the NFPA 90B. For copies, contact the

National Fire Protection Association Inc., Batterymarch Park, Quincy,

MA 02269; (www.NFPA.org) or for only the NFGC, contact the

American Gas Association, 400 N. Capitol Street, N.W., Washington,

DC 20001 (www.AGA.org.).

Combustion and Ventilation Air

Section 9.3 NFPA 54/ANSI Z223.1, Air for Combustion and Ventilation.

WARNING

FIRE HAZARD

Failure to follow this warning could result in personal injury, death

and/or property damage.

Do not install the furnace on its back or hang furnace with control

compartment facing downward. Safety control operation will be

adversely affected. Never connect return-air ducts to the back of the

furnace, see Fig. 4.

80 / 27 C

/ 16 C

WARNING

FIRE, INJURY OR DEATH HAZARD

Failure to follow this warning could result in personal injury, death

and/or property damage.

When the furnace is installed in a residential garage, the burners and

ignition sources must be located at least 18 in. (457 mm) above the

floor. The furnace must be located or protected to avoid damage by

vehicles. When the furnace is installed in a public garage, airplane

hangar, or other building having a hazardous atmosphere, the furnace

must be installed in accordance with the NFPA 54/ANSI Z223.1, see

Fig. 5.

18-IN. (457.2 mm)

MINIMUM TO BURNERS

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

Duct Systems

Air Conditioning Contractors Association (ACCA) Manual D, Sheet

Metal and Air Conditioning Contractors National Association

(SMACNA), or American Society of Heating, Refrigeration, and Air

Conditioning Engineers (ASHRAE) 2001 Fundamentals Handbook

Chapter 34 or 2000 HVAC Systems and Equipment Handbook Chapters

9 and 16.

Acoustical Lining and Fibrous Glass Duct

Current edition of SMACNA and NFPA 90B as tested by UL Standard

181 for Class I Rigid Air Ducts.

Gas Piping and Gas Pipe Pressure Testing

NFPA 54/ANSI Z223.1; Chapters 5, 6, and 7 and National Plumbing

Codes.

Electrical Connections

National Electrical Code (NEC) ANSI/NFPA70.

Venting

NFPA 54/ANSI Z223.1; Chapters 12 and 13.

ELECTROSTATIC DISCHARGE (ESD)

PRECAUTIONS PROCEDURE

1. Disconnect all power to the furnace. Multiple disconnects may be

required. DO NOT TOUCH THE CONTROL OR ANY WIRE

CONNECTED TO THE CONTROL PRIOR TO DISCHARGING

YOUR BODY’S ELECTROSTATIC CHARGE TO GROUND.

2. Firmly touch the clean, unpainted, metal surface of the furnace

chassis which is close to the control. Tools held in a person’s hand

during grounding will be satisfactorily discharged.

3. After touching the chassis, you may proceed to service the control

or connecting wires as long as you do nothing to recharge your

body with static electricity (for example; DO NOT move or shuffle

your feet, do not touch ungrounded objects, etc.).

4. If you touch ungrounded objects (and recharge your body with

static electricity), firmly touch a clean, unpainted metal surface of

the furnace again before touching control or wires.

5. Use this procedure for installed and uninstalled (ungrounded)

furnaces.

6. Before removing a new control from its container, discharge your

body’s electrostatic charge to ground to protect the control from

damage. If the control is to be installed in a furnace, follow items 1

through 4 before bringing the control or yourself in contact with the

furnace. Put all used and new controls into containers before

touching ungrounded objects.

7. An ESD service kit (available from commercial sources) may also

be used to prevent ESD damage.

LOCATION

GENERAL

This multipoise furnace is shipped in packaged configuration. Some

assembly and modifications are required when used in any of four

applications, see in Fig. 6.

CAUTION

FURNACE RELIABILITY HAZARD

Failure to follow this caution may result in unit component damage.

Electrostatic discharge can affect electronic components. Take

precautions during furnace installation and servicing to protect the

furnace electronic control. Precautions will prevent electrostatic

discharges from personnel and hand tools which are held during the

procedure. These precautions will help to avoid exposing the control to

electrostatic discharge by putting the furnace, the control, and the

person at the same electrostatic potential.

CAUTION

PERSONAL INJURY AND/OR PROPERTY

DAMAGE HAZARD

Improper use or installation of this furnace may result in premature

furnace component failure. This gas furnace may be used for heating

buildings under construction provided that:

– The furnace is permanently installed with all electrical wiring, piping,

venting and ducting installed according to these installation

instructions. A return air duct is provided, sealed to the furnace casing,

and terminated outside the space containing the furnace. This prevents

a negative pressure condition as created by the circulating air blower,

causing a flame rollout and/or drawing combustion products into the

structure.

– The furnace is controlled by a thermostat. It may not be “hot wired”

to provide heat continuously to the structure without thermostatic

control.

– Clean outside air is provided for combustion. This is to minimize the

corrosive effects of adhesives, sealers and other construction materials.

It also prevents the entrainment of drywall dust into combustion air,

which can cause fouling and plugging of furnace components.

– The temperature of the return air to the furnace is maintained between

55°F (13°C) and 80°F (27°C), with no evening setback or shutdown.

The use of the furnace while the structure is under construction is

deemed to be intermittent operation per our installation instructions.

– The air temperature rise is within the rated rise range on the furnace

rating plate, and the gas input rate has been set to the nameplate value.

– The filters used to clean the circulating air during the construction

process must be either changed or thoroughly cleaned prior to

occupancy.

– The furnace, ductwork and filters are cleaned as necessary to remove

drywall dust and construction debris from all HVAC system

components after construction is completed.

– Verify proper furnace operating conditions including ignition, gas

input rate, air temperature rise, and venting according to these

installation instructions.

WARNING

CARBON MONOXIDE POISONING / COMPONENT

DAMAGE HAZARD

Failure to follow this warning could result in personal injury or death

and unit component damage.

Corrosive or contaminated air may cause failure of parts containing flue

gas, which could leak into the living space. Air for combustion must not

be contaminated by halogen compounds, which include fluoride,

chloride, bromide, and iodide. These elements can corrode heat

exchangers and shorten furnace life. Air contaminants are found in

aerosol sprays, detergents, bleaches, cleaning solvents, salts, air

fresheners, and other household products. Do not install furnace in a

corrosive or contaminated atmosphere. Make sure all combustion and

circulating air requirements are met, in addition to all local codes and

ordinances.

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

A02097

Fig. 6 – Multipoise Orientations

NOTE: For high-altitude installations, the high-altitude conversion kit

MUST be installed at or above 5500 ft. (1676 M) above sea level. Obtain

high-altitude conversion kit from your area authorized distributor.

This furnace must:

• be installed so the electrical components are protected from water.

• not be installed directly on any combustible material other than

wood flooring (refer to SAFETY CONSIDERATIONS).

• be located close to the chimney or vent and attached to an air

distribution system. Refer to Air Ducts section.

• be provided ample space for servicing and cleaning. Always

comply with minimum fire protection clearances shown on the

furnace clearance to combustible construction label.

The following types of furnace installations may require OUTDOOR

AIR for combustion due to chemical exposures:

• Commercial buildings

• Buildings with indoor pools

• Laundry rooms

• Hobby or craft rooms, and

• Chemical storage areas

If air is exposed to the following substances, it should not be used for

combustion air, and outdoor air may be required for combustion:

• Permanent wave solutions

• Chlorinated waxes and cleaners

• Chlorine based swimming pool chemicals

• Water softening chemicals

• De-icing salts or chemicals

• Carbon tetrachloride

• Halogen type refrigerants

• Cleaning solvents (such as perchloroethylene)

• Printing inks, paint removers, varnishes, etc.

• Hydrochloric acid

• Cements and glues

• Antistatic fabric softeners for clothes dryers

• Masonry acid washing materials

All fuel-burning equipment must be supplied with air for fuel

combustion. Sufficient air must be provided to avoid negative pressure

in the equipment room or space. A positive seal must be made between

the furnace cabinet and the return-air duct to prevent pulling air from the

burner area and from draft safeguard opening.

AIR FOR COMBUSTION AND VENTILATION

Provisions for adequate combustion, ventilation, and dilution air must be

provided in accordance with:

• U.S. Installations: Section 9.3 of the NFPA 54/ANSI Z223.1, Air

for Combustion and Ventilation and applicable provisions of the

local building codes.

The requirements for combustion and ventilation air depend upon

whether or not the furnace is located in a space having a volume of at

least 50 cubic feet per 1,000 Btuh input rating for all gas appliances

installed in the space.

• Spaces having less than 50 cubic feet per 1,000 Btuh require the

OUTDOOR COMBUSTION AIR METHOD.

• Spaces having at least 50 cubic feet per 1,000 Btuh may use the

INDOOR COMBUSTION AIR, STANDARD or KNOWN AIR

INFILTRATION METHOD.

Minimum dimensions of 3-in. (76 mm).

NOTE: Use any of the following combinations of openings:

A & B C & D D & E F & G

A03174

Fig. 7 – Air for Combustion, Ventilation, and Dilution for Outdoors

Outdoor Combustion Air Method

1. Provide the space with sufficient air for proper combustion,

ventilation, and dilution of flue gases using permanent horizontal or

vertical duct(s) or opening(s) directly communicating with the

outdoors or spaces that freely communicate with the outdoors.

2. Fig. 7 illustrates how to provide TWO OUTDOOR OPENINGS,

one inlet and one outlet combustion and ventilation air opening, to

the outdoors.

a. One opening MUST commence within 12 in. (300 mm) of the

ceiling and the second opening MUST commence within 12 in.

(300 mm) of the floor.

CAUTION

FURNACE CORROSION HAZARD

Failure to follow this caution may result in furnace damage.

Air for combustion must not be contaminated by halogen compounds,

which include fluoride, chloride, bromide, and iodide. These elements

can corrode heat exchangers and shorten furnace life. Air contaminants

are found in aerosol sprays, detergents, bleaches, cleaning solvents,

salts, air fresheners, and other household products.

THE BLOWER IS LOCATED

TO THE RIGHT OF THE

BURNER SECTION, AND

AIR CONDITIONED AIR IS

DISCHARGED TO THE LEFT.

THE BLOWER IS

LOCATED BELOW THE

BURNER SECTION, AND

CONDITIONED AIR IS

DISCHARGED UPWARD.

THE BLOWER IS

LOCATED ABOVE THE

BURNER SECTION, AND

CONDITIONED AIR IS

DISCHARGED DOWNWARD

THE BLOWER IS

LOCATED TO THE LEFT

OF THE BURNER SECTION,

AND CONDITIONED AIR IS

DISCHARGED TO THE RIGHT.

WARNING

CARBON MONOXIDE POISONING HAZARD

Failure to follow this warning could result in personal injury or death.

The operation of exhaust fans, kitchen ventilation fans, clothes dryers,

attic exhaust fans or fireplaces could create a NEGATIVE PRESSURE

CONDITION at the furnace. Make-up air MUST be provided for the

ventilation devices, in addition to that required by the furnace. Refer to

the Carbon Monoxide Poisoning Hazard warning in the venting section

of these instructions to determine if an adequate amount of make-up air

is available.

1 SQ IN.

PER

4000

BTUH*

DUCTS

OUTDOORS

1 SQ IN.

PER 4000

BTUH*

CIRCULATING

AIR DUCTS

VENT

THROUGH

ROOF

1 SQ IN.

PER 4000

BTUH*

DUCT

OUTDOORS

CIRCULATING AIR DUCTS

1 SQ IN.

PER 2000

BTUH*

1 SQ IN.

PER 2000

BTUH*

DUCTS

OUTDOORS

12″ MAX

12″

MAX

12″

MAX

OUTDOORS

1 SQ IN.

PER

4000

BTUH*

CLEARANCE IN FRONT

OF COMBUSTION AIR

OPENINGS SHALL BE

AT LEAST 3 IN.

(305mm)

(76mm)

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

b. Size openings and ducts per Fig. 7 and Table 1.

c. TWO HORIZONTAL DUCTS require 1 sq. in. (645 sq. mm) of

free area per 2,000 Btuh (1,100 mm

/kW) of combined input for

all gas appliances in the space per Fig. 7 and Table 1.

d. TWO OPENINGS OR VERTICAL DUCTS require 1 sq. in.

(645 sq. mm) of free area per 4,000 Btuh (550 mm

/kW) for

combined input of all gas appliances in the space per Fig. 7 and

Table 1.

3. ONE OUTDOOR OPENING requires:

a. 1 sq. in. (645 sq. mm) of free area per 3,000 Btuh (734 mm

/kW)

for combined input of all gas appliances in the space per Table 1

and

b. Not less than the sum of the areas of all vent connectors in the

space.

NP = Not Permitted

The opening shall commence within 12 in. (300 mm) of the ceiling.

Appliances in the space shall have clearances of at least 1 in. (25 mm)

from the sides and back and 6 in. (150 mm) from the front. The opening

shall directly communicate with the outdoors or shall communicate

through a vertical or horizontal duct to the outdoors or spaces (crawl or

attic) that freely communicate with the outdoors.

• Indoor Combustion Air

NFPA & AGA

• Standard and Known-Air-Infiltration Rate Methods

• Indoor air is permitted for combustion, ventilation, and dilution, if

the Standard or Known-Air-Infiltration Method is used.

The Standard Method:

Use the Standard Method if:

1. The space has no less volume than 50 cubic feet per 1,000 Btuh of

the maximum input ratings for all gas appliances installed in the

space and

2. The air infiltration rate is not known to be less than 0.40 air changes

per hour (ACH).

Table 1 – Minimum Free Area Required for Each Combustion Air opening of Duct to Outdoors

FURNACE

INPUT

(BTUH)

TWO HORIZONTAL DUCTS SINGLE DUCT OR OPENING TWO OPENINGS OR VERTICAL DUCTS

(1 SQ. IN./2,000 BTUH) (1,100 SQ. MM/KW) (1 SQ. IN./3,000 BTUH) (734 SQ. MM/KW) (1 SQ. IN./4,000 BTUH) (550 SQ. MM/KW)

Free Area of Opening and

Duct

Sq. In. (Sq. mm)

Round Duct Dia.

In. (mm)

Free Area of Opening and

Duct

Sq. In. (Sq. mm)

Round Duct Dia.

In. (mm)

Free Area of Opening and

Duct

Sq. In. (Sq. mm)

Round Duct Dia.

In. (mm)

44,000 22 (14194) 6 (152) 14.7 (9484) 5 (127) 11 (7096) 4 (102)

66,000 33 (21290) 7 (178) 22 (14193) 6 (152) 16.5 (10645) 5 (127)

88,000 44 (28387) 8 (203) 29.3 (18903) 7 (178) 22 (14193) 6 (152)

110,000 55 (35484) 9 (229) 36.7 (23677) 7 (178) 27.5 (17742) 6 (152)

132,000 66 (42580) 10 (254) 44 (28387) 8 (203) 33 (21290) 7 (178)

EXAMPLES: DETERMINING FREE AREA

FURNACE WATER HEATER TOTAL INPUT

110,000 + 30,000 = (140,000 divided by 4,000) = 35.0 Sq. In. for each two Vertical Ducts or Openings

66,000 + 40,000 = (106,000 divided by 3,000) =

35.3 Sq. In. for a Single Duct or Opening

88,000 + 30,000 = (118,000 divided by 2,000) =

59.0 Sq. In. for each of two Horizontal Ducts

Table 2 – Minimum Space Volumes for 100% Combustion, Ventilation, and Dilution from Indoors

OTHER THAN FAN-ASSISTED TOTAL

(1,000’S BTUH GAS INPUT RATE)

FAN-ASSISTED TOTAL

(1,000’S BTUH GAS INPUT RATE)

ACH

30 40 50 44 66 88 110 132 154

Space Volume Ft

)

0.60

1,050

(29.7)

1,400

(39.6)

1,750

(49.5)

1,100

(31.1)

1,650

(46.7)

2,200

(62.2)

2,750

(77.8)

3,300

(93.4)

3,850

(109.0)

0.50

1,260

(35.6)

1,680

(47.5)

2,100

(59.4)

1,320

(37.3)

1,980

(56.0)

2,640

(74.7)

3,300

(93.4)

3,960

(112.1)

4,620

(130.8)

0.40

1,575

(44.5)

2,100

(59.4)

2,625

(74.3)

1,650

(46.7)

2,475

(70.0)

3,300

(93.4)

4,125

(116.8)

4,950

(140.1)

5,775

(163.5)

0.30

2,100

(59.4)

2,800

(79.2)

3,500

(99.1)

2,200

(62.2)

3,300

(93.4)

4,400

(124.5)

5,500

(155.7)

6,600

(186.8)

7,700

(218.0)

0.20

3,150

(89.1)

4,200

(118.9)

5,250

(148.6)

3,300

(93.4)

4,950

(140.1)

6,600

(186.8)

8,250

(233.6)

9,900

(280.3)

11,550

(327.0)

0.10

6,300

(178.3)

8,400

(237.8)

10,500

(297.3)

6,600

(186.8)

9,900

(280.3)

13,200

(373.7)

16,500

(467.2)

19,800

(560.6)

23,100

(654.1)

0.00 NP NP NP NP NP NP NP NP NP

WARNING

CARBON MONOXIDE POISONING HAZARD

Failure to follow this warning could result in personal injury or death.

Many homes require air to be supplied from outdoors for furnace

combustion, ventilation, and dilution of flue gases.

The furnace combustion air supply must be provided in accordance

with this instruction manual.

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

Use the Known Air Infiltration Rate Method if the infiltration rate is

known to be:

1. Less than 0.40 ACH and

2. Equal to or greater than 0.10 ACH

Infiltration rates greater than 0.60 ACH shall not be used. The minimum

required volume of the space varies with the number of ACH and shall

be determined per Table 2 or Equations 1 and 2. Determine the minimum

required volume for each appliance in the space and add the volumes

together to get the total minimum required volume for the space.

Table 2 - Minimum Space Volumes were determined by using the

following equations from the National Fuel Gas Code ANSI

Z223.1/NFPA 54, 9.3.2.2:

1. For other than fan-assisted appliances, such as a draft

hood-equipped water heater, use the following equation:

A04002

2. For fan-assisted appliances such as this furnace, use the following

equation:

A04003

If the following is applied to either equation:

other = combined input of all other than fan-assisted appliances in

Btuh/hr

fan = combined input of all fan-assisted appliances in Btuh/hr

ACH = air changes per hour (ACH shall not exceed 0.60.)

* Minimum opening size is 100 sq in. (64516 sq. mm) with minimum dimensions of 3 in.

(76 mm)

† Minimum of 3 in. (76 mm) when type-B1 vent is used.

A03175

Fig. 8 – Air for Combustion, Ventilation, and Dilution from Indoors

Then the following requirements apply to both the Standard Method

and to the Known Air Infiltration Rate Method:

1. Adjoining rooms can be considered part of a space if:

a. There are no closeable doors between rooms.

b. Combining spaces on same floor level. Each opening shall have

free area of at least 1 in.

/1,000 Btuh (2,000 mm

/kW) of the

total input rating of all gas appliances in the space, but not less

than 100 in.

(0.06 m2). One opening shall commence within 12

in. (300 mm) of the ceiling and the second opening shall

commence within 12 in. (300 mm) of the floor. The minimum

dimension of air openings shall be at least 3 in. (80 mm), see

Fig. 8.

c. Combining space on different floor levels. The volumes of

spaces on different floor levels shall be considered as

communicating spaces if connected by one or more permanent

openings in doors or floors having free area of at least 2

in.

/1,000 Btuh (4,400 mm

/kW) of total input rating of all gas

appliances

2. An attic or crawlspace may be considered a space that freely

communicates with the outdoors provided there are adequate

permanent ventilation openings directly to outdoors having free

area of at least 1-in.

/4,000 Btuh of total input rating for all gas

appliances in the space.

3. In spaces that use the Indoor Combustion Air Method, infiltration

should be adequate to provide air for combustion, permanent

ventilation and dilution of flue gases. However, in buildings with

unusually tight construction, additional air MUST be provided

using the methods described in the Outdoor Combustion Air

Method section.

4. Unusually tight construction is defined as Construction with:

a. Walls and ceilings exposed to the outdoors have a continuous,

sealed vapor barrier. Openings are gasketed or sealed and

b. Doors and openable windows are weatherstripped and

c. Other openings are caulked or sealed. These include joints

around window and door frames, between sole plates and floors,

between wall-ceiling joints, between wall panels, at penetrations

for plumbing, electrical and gas lines, etc.

Combination of Indoor and Outdoor Air

1. Indoor openings shall comply with the Indoor Combustion Air

Method below and,

2. Outdoor openings shall be located as required in the Outdoor

Combustion Air Method mentioned previously and,

3. Outdoor openings shall be sized as follows:

a. Calculate the Ratio of all Indoor Space volume divided by

required volume for Indoor Combustion Air Method below.

b. Outdoor opening size reduction Factor is 1 minus the Ratio in a.

above.

c. Minimum size of Outdoor openings shall be the size required in

Outdoor Combustion Air Method above multiplied by reduction

Factor in b. above. The minimum dimension of air openings shall

be not less than 3 in. (80 mm).

INSTALLATION

UPFLOW INSTALLATION

Bottom Return Air Inlet

These furnaces are shipped with bottom closure panel installed in bottom

return-air opening. Remove and discard this panel when bottom return

air is used. To remove bottom closure panel, perform the following:

1. Tilt or raise furnace and remove 2 screws holding bottom filler

panel, see Fig. 9.

2. Rotate bottom filler panel downward to release holding tabs.

3. Remove bottom closure panel.

4. Reinstall bottom filler panel and screws.

A10273

Fig. 9 – Removing Bottom Closure Panel

Volume

Other

21ft

ACH

other

1000 Btu/hr

Volume

Fan

15ft

ACH

fan

1000 Btu/hr

CIRCULATING AIR

DUCTS

6" MIN

(FRONT)

CIRCULATING AIR DUCTS

VENT THROUGH ROOF

1 SQ IN.

PER 1000

BTUH* IN DOOR

OR WALL

12" MAX

1 SQ IN.

PER 1000

BTUH* IN DOOR

OR WALL

12" MAX

UNCONFINED

SPACE

INTERIOR

HEATED

SPACE

CLEARANCE IN FRONT OF COMBUSTION AIR

O PE NI N GS S HA LL BE AT LEAST 3 IN.

(305mm)

(152mm)

(305mm)

Bottom

Closure Panel

Bottom Filler Panel

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

Side Return Air Inlet

These furnaces are shipped with bottom closure panel installed in bottom

return-air opening. This panel MUST be in place when only side return

air is used.

NOTE: Side return-air openings can be used in UPFLOW and most

HORIZONTAL configurations. Do not use side return-air openings in

DOWNFLOW configuration.

DOWNFLOW INSTALLATION

NOTE: For downflow applications, this furnace is approved for use on

combustible flooring when any one of the following accessories are

used:

• Special Base, KGASB

• Cased Coil Assembly Part No. CNPV, CNRV, CAP, or CAR

• Coil Box Part No. KCAKC

1. Determine application being installed from Table 3.

2. Construct hole in floor, see Table 3 and Fig. 10.

3. Construct plenum to dimensions specified, see Table 3 and Fig. 10.

4. If downflow subbase, KGASB is used, install, see Fig. 11. If Coil

Assembly Part No. CPVP, CAPMP or CNPVP Coil Box Part No.

KCAKC is used, install, see Fig. 12.

NOTE: It is recommended that the perforated supply-air duct flanges be

completely folded over or removed from furnace when installing the

furnace on a factory-supplied cased coil or coil box. To remove the

supply-air duct flange, use wide duct pliers or hand seamers to bend

flange back and forth until it breaks off. Be careful of sharp edges. Refer

to Duct Flanges (Fig. 17) in the “Air Ducts” section.

Bottom Return Air Inlet

These furnaces are shipped with bottom closure panel installed in bottom

return-air opening. Remove and discard this panel when bottom return

air is used. To remove bottom closure panel, perform the following:

1. Tilt or raise furnace and remove 2 screws holding bottom filler

panel, Fig. 9.

2. Rotate bottom filler panel downward to release holding tabs.

3. Remove bottom closure panel.

4. Reinstall bottom filler panel and screws.

A96283

Fig. 10 – Floor and Plenum Opening Dimensions

A96285

Fig. 11 – Furnace, Plenum, and Subbase Installed on a Combustible

Floor

A08556

Fig. 12 – Furnace, Plenum, and Coil Assembly or Coil Box Installed

on a Combustible Floor

HORIZONTAL INSTALLATION

The furnace can be installed horizontally in an attic or crawlspace on

either the left-hand (LH) or right-hand (RH) side. The furnace can be

hung from floor joists, rafters or trusses or installed on a

non-combustible platform, blocks, bricks or pad.

Suspended Furnace Support

The furnace may be supported under each end with threaded rod, angle

iron or metal plumber’s strap as shown, see Fig. 14 and Fig. 15. Secure

angle iron to bottom of furnace as shown. Heavy-gauge sheet metal

straps (plumber’s straps) may be used to suspend the furnace from each

bottom corner. To prevent screws from pulling out, use 2 #8 x in. screws

into the side and 2 #8 x in. screws in the bottom of the furnace casing for

each strap, see Fig. 14 and Fig. 15.

If the screws are attached to ONLY the furnace sides and not the bottom,

the straps must be vertical against the furnace sides and not pull away

from the furnace sides, so that the strap attachment screws are not in

tension (are loaded in shear) for reliable support.

Platform Furnace Support

Construct working platform at location where all required furnace

clearances are met, see Fig. 2 and Fig. 13. For furnaces with 1-in. (25

mm) clearance requirement on side, set furnace on non-combustible

blocks, bricks or angle iron. For crawlspace installations, if the furnace

is not suspended from the floor joists, the ground underneath furnace

must be level and the furnace set in blocks or bricks.

PLENUM

OPENING

FLOOR

OPENING

DOWNFLOW

SUBBASE

SHEET METAL

PLENUM

FLOOR

OPENING

FURNACE

(OR COIL CASING

WHEN USED)

COMBUSTIBLE

FLOORING

APPROVED

COIL ASSEMBLY

COIL BOX

FURNACE

SHEET METAL

PLENUM

FLOOR

OPENING

COMBUSTIBLE

FLOORING

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

Roll-Out Protection

Provide a minimum 17-3/4-in. X 22-in. (451 X 559 mm) piece of sheet

metal for flame roll-out protection in front of burner area for furnaces

closer than 12-in. (305 mm) above the combustible deck or suspended

furnaces closer than 12-in. (305 mm) to joists. The sheet metal MUST

extend underneath the furnace casing by 1-in. (25 mm) with the door

removed.

The bottom closure panel on furnaces of widths 17-1/2-in. (445 mm) and

larger may be used for flame roll-out protection when bottom of furnace

is used for return air connection. See Fig. 13 for proper orientation of

roll-out shield.

Bottom Return Air Inlet

These furnaces are shipped with bottom closure panel installed in bottom

return-air opening. Remove and discard this panel when bottom return

air is used. To remove bottom closure panel, perform the following:

1. Tilt or raise furnace and remove two screws holding bottom filler

panel, see Fig. 9.

2. Rotate bottom filler panel downward to release holding tabs.

3. Remove bottom closure panel.

4. Reinstall bottom filler panel and screws.

A10164

Fig. 13 – Typical Attic Installation

Side Return Air Inlet

These furnaces are shipped with bottom closure panel installed in bottom

return-air opening. This panel MUST be in place when side return air

inlet(s) are used without a bottom return air inlet.

Not all horizontal furnaces are approved for side return air connections,

see Fig. 20.

Table 3 – Opening Dimensions - In. (mm)

FURNACE

CASING

WIDTH

IN. (mm)

APPLICATION

PLENUM OPENING FLOOR OPENING

A B C D

14–3/16

(360)

Upflow Applications on Combustible or Noncombustible

Flooring (subbase not required)

12-11/16

(322)

21-5/8

(549)

13-5/16

(338)

22-1/4

(565)

Downflow Applications on Noncombustible Flooring

(subbase not required)

12-9/16

(319)

(483)

13-3/16

(335)

19-5/8

(498)

Downflow applications on Combustible Flooring

(subbase required)

11-13/16

(284)

(483)

13-7/16

(341)

20-5/8

(600)

Downflow Applications on Combustible Flooring with coil assembly or coil

box (subbase not required)

12-5/16

(319)

(483)

13-5/16

(338)

(508)

17–1/2

(445)

Upflow Applications on Combustible or Noncombustible

Flooring (subbase not required)

(406)

21-5/8

(549)

16-5/8

(422)

22-1/4

(565)

Downflow Applications on Noncombustible Flooring

(subbase not required)

15-7/8

(403)

(483)

16-1/2

(419)

19-5/8

(498)

Downflow Applications on Combustible Flooring

(subbase required)

15-1/8

(384)

(483)

16-3/4

(425)

20-5/8

(600)

Downflow Applications on Combustible Flooring with coil assembly or coil

box (subbase not required)

15-1/2

(394)

(483)

16-1/2

(419)

(508)

(533)

Upflow Applications on Combustible or Noncombustible

Flooring (subbase not required)

19-1/2

(495)

21-5/8

(549)

20-1/8

(511)

22-1/4

(565)

Downflow Applications on Noncombustible Flooring

(subbase not required)

19-3/8

(492)

(483)

(508)

19-5/8

(498)

Downflow Applications on Combustible Flooring

(subbase required)

18-5/8

(473)

(483)

20-1/4

(514)

20-5/8

(600)

Downflow Applications on Combustible Flooring with coil assembly or coil

box (subbase not required)

(483)

(508)

24-1/2

(622)

Upflow Applications on Combustible or Noncombustible

Flooring (subbase not required)

(584)

21-1/8

(537)

23-5/8

(600)

22-1/4

(565)

Downflow Applications on Noncombustible Flooring

(subbase not required)

22-7/8

(581)

(483)

23-1/2

(597)

19-5/8

(498)

Downflow Applications on Combustible Flooring

(subbase required)

22-1/8

(562)

(483)

23-3/4

(603)

20-5/8

(600)

Downflow Applications on Combustible Flooring with coil assembly or coil

box (subbase not required)

22-1/2

(572)

(483)

23-1/2

(597)

(508)

30-IN. (762mm)

MIN WORK AREA

6″ MIN*

TYPE-B

VENT

″

SHEET

METAL

SEDIMENT

TRAP

EQUIPMENT MANUAL

SHUT-OFF GAS VALVE

LINE CONTACT ONLY PERMISSIBLE BETWEEN

LINES FORMED BY INTERSECTIONS OF

THE TOP AND TWO SIDES OF THE FURNACE

JACKET AND BUILDING JOISTS,

STUDS, OR FRAMING.

GAS

ENTRY

″

(451mm)

OVERALL

″

(121mm)

UNDER DOOR

1″

(25mm)

UNDER FURNACE

EXTEND OUT 12″

(305mm)

FROM FACE OF DOOR

* WHEN USED WITH

SINGLE WALL VENT

CONNECTIONS

UNION

(152mm)

(451mm)

(559mm)

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

A10130

Fig. 14 – Horizontal Unit Suspension

A10131

Fig. 15 – Horizontal Suspension with Straps

FILTER ARRANGEMENT

There are no provisions for an internal filter rack in these furnaces. A

field-supplied accessory external filter rack is required.

Refer to the instructions supplied with the external filter rack for

assembly and installation options.

Leveling Legs (If Desired)

In upflow position with side return inlet(s), leveling legs may be used,

see Fig. 16. Install field-supplied, 5/16 X 1-1/2 in. (8 X 38 mm) (max)

corrosion-resistant machine bolts, washers and nuts.

A89014

Fig. 16 – Leveling Legs

NOTE: Bottom closure must be used when leveling legs are used. It

may be necessary to remove and reinstall bottom closure panel to install

leveling legs. To remove bottom closure panel, see Item 1 in “Bottom

Return Air Inlet” section in Step 1 above.

To install leveling legs:

1. Position furnace on its back. Locate and drill a hole in each bottom

corner of furnace, see Fig. 16.

2. For each leg, install nut on bolt and then install bolt with nut in

hole. (Install flat washer if desired.)

3. Install another nut on other side of furnace base. (Install flat washer

if desired.)

4. Adjust outside nut to provide desired height, and tighten inside nut

to secure arrangement.

5. Reinstall bottom closure panel if removed.

LOCATION RELATIVE TO COOLING EQUIPMENT

The cooling coil must be installed parallel with, or on the downstream

side of the unit to avoid condensation in the heat exchangers. When

installed parallel with the furnace, dampers or other flow control must

prevent chilled air from entering the furnace. If the dampers are

manually operated, they must be equipped with means to prevent

operation of either unit unless the damper is in the full-heat or full-cool

position.

AIR DUCTS

GENERAL REQUIREMENTS

The duct system should be designed and sized according to accepted

national standards such as those published by: Air Conditioning

Contractors Association (ACCA), Sheet Metal and Air Conditioning

Contractors National Association (SMACNA) or American Society of

Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) or

consult The Air Systems Design Guidelines reference tables available

from your local distributor. The duct system should be sized to handle

the required system design CFM at the design external static pressure.

The furnace airflow rates are provided in Table 13-Air Delivery-CFM

(With Filter). When a furnace is installed so that the supply ducts carry

air circulated by the furnace to areas outside the space containing the

WARNING

FIRE, EXPLOSION, AND CARBON MONOXIDE

POISONING HAZARD

Failure to follow this warning could result in personal injury, death, or

property damage.

Do not install the furnace on its back or hang furnace with control

compartment facing downward. Safety control operation will be

adversely affected. Never connect return-air ducts to the back of the

furnace.

WARNING

CARBON MONOXIDE POISONING HAZARD

Failure to follow this warning could result in personal injury, or death.

Never operate a furnace without a filter or with filter access door

removed.

/4" (6mm) THREADED ROD

4 REQ.

SECURE ANGLE

IRON TO BOTTOM

OF FURNACE WITH

3 #8 x

/4" (19mm) SCREWS

TYPICAL FOR 2 SUPPORTS

1” (25mm) SQUARE, 1-1/4”x1-1/4”x1/8” (32x32x3mm)

ANGLE IRON OR UNI-STRUT MAY BE USED

(2) HEX NUTS, (2) WASHERS & (2) LOCK WASHERS

REQ. PER ROD

8" (203mm)

MIN

FOR DOOR REMOVAL

OUTER DOOR

ASSEMBLY

METHOD 2

USE (4) #8 x 3/4 (19 mm) SHEET

METAL SCREWS FOR EACH

STRAP. THE STRAPS

SHOULD BE VERTICAL

AGAINST THE FURNACE

SIDES AND NOT PULL AWAY

FROM THE FURNACE

SIDES.

METHOD 1

FOLD ALL STRAPS UNDER

FURNACE AND SECURE WTH

(4) #8 x 3/4 (19 mm) SHEET METAL SCREWS

(2 SCREWS IN SIDE AND 2 SCREWS

IN BOTTOM).

(44mm)

(8mm)

(44mm)

(8mm)

(44mm)

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

furnace, the return air shall also be handled by duct(s) sealed to the

furnace casing and terminating outside the space containing the furnace.

Secure ductwork with proper fasteners for type of ductwork used. Seal

supply- and return-duct connections to furnace with code approved tape

or duct sealer.

NOTE: Flexible connections should be used between ductwork and

furnace to prevent transmission of vibration.

Ductwork passing through unconditioned space should be insulated to

enhance system performance. When air conditioning is used, a vapor

barrier is recommended.

Maintain a 1-in. (25 mm) clearance from combustible materials to

supply air ductwork for a distance of 36-in. (914 mm) horizontally from

the furnace. See NFPA 90B or local code for further requirements

Ductwork Acoustical Treatment

NOTE: Metal duct systems that do not have a 90 degree elbow and 10

ft. (3 M) of main duct to the first branch take-off may require internal

acoustical lining. As an alternative, fibrous ductwork may be used if

constructed and installed in accordance with the latest edition of

SMACNA construction standard on fibrous glass ducts. Both acoustical

lining and fibrous ductwork shall comply with NFPA 90B as tested by

UL Standard 181 for Class 1 Rigid air ducts.

SUPPLY AIR CONNECTIONS

For a furnace not equipped with a cooling coil, the outlet duct shall be

provided with a removable access panel. This opening shall be

accessible when the furnace is installed and shall be of such a size that

the heat exchanger can be viewed for possible openings using light

assistance or a probe can be inserted for sampling the air stream. The

cover attachment shall prevent leaks.

Upflow and Horizontal Furnaces

Connect supply-air duct to flanges on furnace supply-air outlet. Bend

flange upward to 90° with wide duct pliers, see Fig. 17. The supply-air

duct must be connected to ONLY the furnace supply-outlet-air duct

flanges or air conditioning coil casing (when used). DO NOT cut main

furnace casing side to attach supply air duct, humidifier, or other

accessories. All accessories MUST be connected to duct external to

furnace main casing.

NOTE: For horizontal applications, the top most flange may be bent

past 90° to allow the evaporator coil to hang on the flange temporarily

while the remaining attachment and sealing of the coil are performed.

Downflow Furnaces

Connect supply-air duct to supply-air outlet on furnace. Bend flange

inward past 90° with wide duct pliers, see Fig. 17. The supply-air duct

must be connected to ONLY the furnace supply outlet or air conditioning

coil casing (when used). When installed on combustible material,

supply-air duct must be connected to ONLY the factory-approved

accessory subbase, or a factory-approved air conditioning coil casing.

DO NOT cut main furnace casing to attach supply side air duct,

humidifier, or other accessories. All accessories MUST be connected to

duct external to furnace casing.

RETURN AIR CONNECTIONS

A190346

Fig. 17 – Duct Flanges

Downflow Furnaces

The return-air duct must be connected to return-air opening bottom inlet,

see Fig. 1. DO NOT cut into casing sides (left or right). Side opening is

permitted for only upflow and certain horizontal furnaces. Bypass

humidifier connections should be made at ductwork or coil casing sides

exterior to furnace, see Fig. 18.

Upflow and Horizontal Furnaces

The return-air duct must be connected to bottom, sides (left or right), or a

combination of bottom and side(s) of main furnace casing, see Fig. 1.

Bypass humidifier may be attached into unused return air side of the

furnace casing, see Fig. 19 and Fig. 20. Not all horizontal furnace

models are approved for side return air connections, see Fig. 20.

WARNING

FIRE HAZARD

A failure to follow this warning could cause personal injury, death

and/or property damage.

Never connect return-air ducts to the back of the furnace. Follow

instructions below.

UPFLOW/

HORIZONTAL

DOWNFLOW

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

A02163

Fig. 18 – Downflow Return Air Configurations and Restrictions

A02075

Fig. 19 – Upflow Return Air Configurations and Restrictions

A02162

Fig. 20 – Horizontal Return Air Configurations and Restrictions

DOWNFLOW RETURN AIR CONFIGURATIONS AND RESTRICTIONS

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

GAS PIPING

Gas piping must be installed in accordance with national and local

codes. Refer to current edition of NFGC in the U.S.

Installations must be made in accordance with all authorities having

jurisdiction. If possible, the gas supply line should be a separate line

running directly from meter to furnace.

NOTE: In the state of Massachusetts:

1. Gas supply connections MUST be performed by a licensed plumber

or gas fitter.

2. When flexible connectors are used, the maximum length shall not

exceed 36 in. (915 mm).

3. When lever handle type manual equipment shutoff valves are used,

they shall be T-handle valves.

4. The use of copper tubing for gas piping is NOT approved by the

state of Massachusetts.

Refer to Table 4 for recommended gas pipe sizing. Risers must be used

to connect to furnace and to meter. Support all gas piping with

appropriate straps, hangers, etc. Use a minimum of 1 hanger every 6 ft.

(1.8 M). Joint compound (pipe dope) should be applied sparingly and

only to male threads of joints. Pipe dope must be resistant to the action

of propane gas.

* Cubic ft of gas per hr for gas pressures of 0.5 psig (14-In. W.C.) or less and a pressure

drop of 0.5-In. W.C. (based on a 0.60 specific gravity gas). Ref: Table 6 and 9.2 NFGC.

An accessible manual equipment shutoff valve MUST be installed

external to furnace casing and within 6 ft. (1.8 M) of furnace. A 1/8-in.

(3 mm) NPT plugged tapping, accessible for test gauge connection,

MUST be installed immediately upstream of gas supply connection to

furnace and downstream of manual equipment shutoff valve.

NOTE: The furnace gas control valve inlet pressure tap connection is

suitable to use as test gauge connection providing test pressure DOES

NOT exceed maximum 0.5 psig (14-In. W.C.) stated on gas control

valve, see Fig. 21.

Some installations require gas entry on right side of furnace (as viewed

in upflow), see Fig. 22.

A04167

Fig. 21 – Redundant Automatic Gas Control Valve

WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal injury, death,

and/or property damage.

Never purge a gas line into a combustion chamber. Never test for gas

leaks with an open flame. Use a commercially available soap solution

made specifically for the detection of leaks to check all connections. A

fire or explosion may result causing property damage, personal injury

or loss of life.

WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal injury, death,

and/or property damage.

Use proper length of pipe to avoid stress on gas control manifold and

gas valve.

WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal injury, death,

and/or property damage.

Gas valve inlet and/or inlet pipe must remain capped until gas supply

line is permanently installed to protect the valve from moisture and

debris. Also, install a sediment trap in the gas supply piping at the inlet

to the gas valve.

Table 4 – Maximum Capacity of Pipe

NOMINAL

IRON PIPE

SIZE

IN. (MM)

INTERNAL

DIA.

IN. (MM)

LENGTH OF PIPE - FT (M)

(3.0)

(6.0)

(9.1)

(12.1)

(15.2)

1/2 (12.7) 0.622(158) 175 120 97 82 73

3/4 (19.0) 0.824 (20.9) 360 250 200 170 151

1 ( 25.4) 1.049 (26.6) 680 465 375 320 285

1-1/4 (31.8) 1.380 (35.0) 1400 950 770 660 580

1-1/2 (38.1) 1.610 (40.9) 2100 1460 1180 990 900

WARNING

FIRE OR EXPLOSION HAZARD

A failure to follow this warning could result in personal injury, death,

and/or property damage.

If local codes allow the use of a flexible gas appliance connector,

always use a new listed connector. Do not use a connector which has

previously served another gas appliance. Black iron pipe shall be

installed at the furnace gas control valve and extend a minimum of 2-in.

(51 mm) outside the furnace.

CAUTION

FURNACE DAMAGE HAZARD

Failure to follow this caution may result in furnace damage.

Connect gas pipe to furnace using a backup wrench to avoid damaging

gas controls and burner misalignment.

REGULATOR COVER SCREW

PLASTIC ADJUST SCREW

LOW STAGE

GAS PRESSURE

REGULATOR ADJUSTMENT

MANIFOLD

PRESSURE TAP

INLET

PRESSURE TAP

ON/OFF SWITCH

REGULATOR SPRING

HIGH STAGE GAS

PRESSURE REGULATOR

ADJUSTMENT

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

A08551

Fig. 22 – Burner and Manifold

Install a sediment trap in riser leading to furnace, see Fig. 23. Connect a

capped nipple into lower end of tee. Capped nipple should extend below

level of furnace gas controls. Place a ground joint union between furnace

gas control valve and exterior manual equipment gas shutoff valve.

A 1/8-in. (3 mm) NPT plugged tapping, accessible for test gauge

connection, MUST be installed immediately upstream of gas supply

connection to furnace and downstream of manual equipment shutoff

valve.

A02035

Fig. 23 – Typical Gas Pipe Arrangement

Piping should be pressure and leak tested in accordance with the current

addition of the NFGC in the United States, local, and national plumbing

and gas codes before the furnace has been connected. After all

connections have been made, purge lines and check for leakage at

furnace prior to operating furnace.

If pressure exceeds 0.5 psig (14-In. W.C.), gas supply pipe must be

disconnected from furnace and capped before and during supply pipe

pressure test. If test pressure is equal to or less than 0.5 psig (14-In.

W.C.), turn off electric shutoff switch located on furnace gas control

valve and accessible manual equipment shutoff valve before and during

supply pipe pressure test. After all connections have been made, purge

lines and check for leakage at furnace prior to operating furnace.

The gas supply pressure shall be within the maximum and minimum

inlet supply pressures marked on the rating plate with the furnace

burners ON and OFF.

ELECTRICAL CONNECTIONS

See Fig. 24 for field wiring diagram showing typical field 115-v wiring.

Check all factory and field electrical connections for tightness.

Field-supplied wiring shall conform with the limitations of 63°F (33°C)

rise.

2” (51mm)

Street Elbow

UNION

SEDIMENT

TRAP

MANUAL

SHUTOFF

VALVE

(REQUIRED)

GAS

SUPPLY

WARNING

ELECTRICAL SHOCK, FIRE OR EXPLOSION HAZARD

Failure to follow safety warnings could result in dangerous operation,

serious injury, death or property damage.

Improper servicing could result in dangerous operation, serious injury,

death or property damage.

- Before servicing, disconnect all electrical power to furnace.

- When servicing controls, label all wires prior to disconnection.

Reconnect wires correctly.

- Verify proper operation after servicing.

WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury or death.

Blower access panel door switch opens 115-v power to control. No

component operation can occur. Do not bypass or close switch with

panel removed.

WARNING

ELECTRICAL SHOCK AND FIRE HAZARD

Failure to follow this warning could result in personal injury, death, or

property damage.

The cabinet MUST have an uninterrupted or unbroken ground

according to NEC NFPA 70 or local codes to minimize personal injury

if an electrical fault should occur. This may consist of electrical wire,

conduit approved for electrical ground or a listed, grounded power cord

(where permitted by local code) when installed in accordance with

existing electrical codes. Refer to the power cord manufacturer’s

ratings for proper wire gauge. Do not use gas piping as an electrical

ground.

CAUTION

FURNACE MAY NOT OPERATE HAZARD

Failure to follow this caution may result in intermittent furnace

operation.

Furnace control must be grounded for proper operation or else control

will lock out. Control must remain grounded through green/yellow wire

routed to gas valve and manifold bracket screw.

WARNING

FIRE HAZARD

Failure to follow this warning could result in personal injury, death, or

property damage.

Do not connect aluminum wire between disconnect switch and furnace.

Use only copper wire, see Fig. 25.

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

A95236

Fig. 24 – Field Wiring Diagram

A190279

Fig. 25 – Field-Supplied External

Electrical Box on Furnace Casing

115-V Wiring

Verify that the voltage, frequency, and phase correspond to that specified

on unit rating plate. Also, check to be sure that service provided by

utility is sufficient to handle load imposed by this equipment. Refer to

rating plate or Table 5 for equipment electrical specifications.

U.S. Installations: Make all electrical connections in accordance with

National Electrical Code (NEC) NFPA 70 and any local codes or

ordinances that might apply.

Use a separate, fused branch electrical circuit with a properly sized fuse

or circuit breaker for this furnace. See Table 5 for wire size and fuse

specifications. A readily accessible means of electrical disconnect must

be located within sight of the furnace.

NOTE: Proper polarity must be maintained for 115-v wiring. If polarity

is incorrect, control LED status indicator light will flash rapidly and

furnace will NOT operate.

J-BOX RELOCATION

NOTE: If factory location of J-Box is acceptable, go to next section

(ELECTRICAL CONNECTION to J-Box).

NOTE: On 14-in. (356 mm) wide casing models, the J-Box shall not be

relocated to other side of furnace casing when the vent pipe is routed

within the casing.

1. Remove and save two screws holding J-Box, see Fig. 26.

NOTE: The J-Box cover need not be removed from the J-Box in order

to move the J-Box. Do NOT remove green ground screw inside J-Box,

see Fig. 26.

2. Cut wire tie on loop in furnace wires attached to J-Box.

3. Move J-Box to desired location.

4. Fasten J-Box to casing with the two screws removed in Step 1.

5. Route J-Box wires within furnace away from sharp edges, rotating

parts and hot surfaces.

Table 5 – Electrical Data

FURNACE

SIZE

VOLTS-

HERTZ-

PHASE

OPERATING

VOLTAGE RANGE

*. Permissible limits of the voltage range at which the unit operates satisfactorily.

MAX.

UNIT

AMPS

UNIT

AMPACITY

†

†. Unit ampacity = 125 percent of largest operating component’s full load amps plus 100 percent of all other potential operating components’ (EAC, humidifier, etc.) full load

amps.

MAX. WIRE LENGTH

- FT (M)

‡

‡. Length shown is as measured 1 way along wire path between furnace and service panel for maximum 2 percent voltage drop.

MAX. FUSE OR CKT

BKR AMPS

**. Time-delay type is recommended.

MIN. WIRE

GAUGE

Max. Min.

36045C17 115-60-1 127 104 9.0 12.0 30 (9.4) 15 14

36070C14 115-60-1 127 104 9.0 12.0 30 (9.4) 15 14

48070C17 115-60-1 127 104 9.0 13.0 28 (8.7) 15 14

60070C21

115-60-1 127 104 14.1 18.4 31 (9.5) 20 12

48090C17

115-60-1 127 104 9.6 12.63 29 (9.0) 15 14

60090C21

115-60-1 127 104 14.7 19.0 30 (9.2) 20 12

60110C21 115-60-1 127 104 15.0 19.3 29 (9.1) 20 12

66135C24

115-60-1 127 104 15.0 19.3 29 (9.1) 20 12

115-VOLT FIELD-

SUPPLIED

FUSED

DISCONNECT

JUNCTION

BOX

CONTROL

BOX

24-VOLT

TERMINAL

BLOCK

THREE-WIRE

HEATING-

ONLY

FIVE

WIRE

NOTE 2

NOTE 1

1-STAGE

THERMOSTAT

TERMINALS

FIELD-SUPPLIED

FUSED DISCONNECT

CONDENSING

UNIT

FURNACE

COM

WCY RG

GND

FIELD 24-VOLT WIRING

FIELD 115-, 208/230-, 460-VOLT WIRING

FACTORY 24-VOLT WIRING

FACTORY 115-VOLT WIRING

Connect Y/Y2-terminal as shown for proper operation.

Some thermostats require a "C" terminal connection as shown.

If any of the original wire, as supplied, must be replaced, use

same type or equivalent wire.

208/230- O

460-VOLT

THREE

PHASE

208/230-

VOLT

SINGLE

PHASE

BLK

WHT

BLK

W/W1

Y/Y2

NOTES: 1.

COPPER

WIRE ONLY

ELECTRIC

DISCONNECT

SWITCH

ALUMINUM

WIRE

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

A10291

Fig. 26 – Relocating J-Box

Electrical Connection to J-Box

Electrical Box on Furnace Casing Side

A190278

Fig. 27 – Field-Supplied Electrical Box on Furnace Casing

1. Select and remove a hole knockout in the casing where the

electrical box is to be installed.

NOTE: Check that duct on side of furnace will not interfere with

installed electrical box.

2. Remove the desired electrical box hole knockout and position the

hole in the electrical box over the hole in the furnace casing.

3. Fasten the electrical box to casing by driving two field-supplied

screws from inside electrical box into casing steel.

4. Remove and save two screws holding J-Box, see Fig. 26.

5. Pull furnace power wires out of 1/2-in. (12 mm) diameter hole in

J-Box. Do not loosen wires from strain-relief wire-tie on outside of

J-Box.

6. Route furnace power wires through holes in casing and electrical

box and into electrical box.

7. Pull field power wires into electrical box.

8. Remove cover from furnace J-Box.

9. Route field ground wire through holes in electrical box and casing,

and into furnace J-Box.

10. Reattach furnace J-Box to furnace casing with screws removed in

Step 4.

11. Secure field ground wire to J-Box green ground screw.

12. Complete electrical box wiring and installation. Connect line

voltage leads, see Fig. 27. Use best practices (NEC in U.S. for wire

bushings, strain relief, etc.

13. Reinstall cover to J-Box. Do not pinch wires between cover and

bracket.

Power Cord Installation in Furnace J-Box

NOTE: Power cords must be able to handle the electrical requirements

listed in Table 5. Refer to power cord manufacturer’s listings.

1. Remove cover from J-Box.

2. Route listed power cord through 7/8-in. (22 mm) diameter hole in

J-Box.

3. Secure power cord to J-Box bracket with a strain relief bushing or a

connector approved for the type of cord used.

4. Secure field ground wire to green ground screw on J-Box bracket.

5. Connect line voltage leads, see Fig. 24.

6. Reinstall cover to J-Box. Do not pinch wires between cover and

bracket.

BX Cable Installation in Furnace J-Box

1. Remove cover from J-Box.

2. Route BX cable into 7/8-in. (22 mm) diameter hole in J-Box.

3. Secure BX cable to J-Box bracket with connectors approved for the

type of cable used.

4. Secure field ground wire to green ground screw on J-Box bracket.

5. Connect line voltage leads, see Fig. 24.

6. Reinstall cover to J-Box. Do not pinch wires between cover and

bracket.

24-V Wiring

Make field 24-v connections at the 24-v terminal strip, see Fig. 24 -

Fig. 35. Connect terminal Y/Y2 as shown in Fig. 28 - Fig. 34 for proper

cooling operation. Use only AWG No. 18, color-coded, copper

thermostat wire.

The 24-v circuit contains an automotive-type, 3-amp. fuse located on the

control. Any direct shorts during installation, service, or maintenance

could cause this fuse to blow. If fuse replacement is required, use ONLY

a 3-amp. fuse of identical size.

ACCESSORIES

1. Electronic Air Cleaner (EAC)

Connect an accessory Electronic Air Cleaner (if used) using 1/4-in

female quick connect terminals to the two male 1/4-in

quick-connect terminals on the control board marked EAC-1 and

EAC-2. The terminals are rated for 115VAC, 1.0 amps maximum

and are energized during blower motor operation, see Fig. 35.

2. Humidifier (HUM)

Connect an accessory 24 VAC, 0.5 amp. maximum humidifier

(if used) to the 1/4-in male quick-connect HUM terminal and

COM-24V screw terminal on the control board thermostat strip.

The HUM terminal is energized when blower is energized in

heating, see Fig. 35.

NOTE: DO NOT connect furnace control HUM terminal to HUM

(humidifier) terminal on Thermostat, Zone Controller or similar device.

See Thermostat, Zone Controller, thermostat, or controller

manufacturer’s instructions for proper connection.

WARNING

FIRE OR ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury, death, or

property damage.

If field-supplied manual disconnect switch is to be mounted on furnace

casing side, select a location where a drill or fastener cannot damage

electrical or gas components.

FactoryFactory

InstalledInstalled

AlternateAlternate

LocationLocation

GROUND

NEUTRAL

INE VOLTAGE

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

A190166

Fig. 28 – Variable Furnace with Single-Speed Air Conditioner

A190170

Fig. 29 – Dual-Fuel Thermostat with Variable Furnace

and Single-Speed Heat Pump

A190167

Fig. 30 – Variable Furnace with Two-Speed Air Conditioner

A190171

Fig. 31 – Dual-Fuel Thermostat with Variable Furnace and

Two-Speed Heat Pump

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

A190168

Fig. 32 – Variable Furnace with Single-Speed Heat Pump

(Dual Fuel)

A190169

Fig. 33 – Variable Furnace with Two-Speed Heat Pump

(Dual Fuel)

A190172

Two-Stage Thermostat with Variable Furnace

and Two-Speed Air Conditioner

A190173

Fig. 34 – Single-Stage Thermostat with Variable Furnace and

Two-Speed Air Conditioner

NOTES FOR FIGURE 28 - FIGURE 35

1. Heat pump MUST have a high pressure switch for dual fuel

applications.

2. Refer to outdoor equipment Installation Instructions for additional

information and setup procedure.

3. If the heat pump date code is 1501E or earlier, select the “ZONE”

position on the two-speed heat pump control.

Heat pumps having date codes 1601E and later do not have or

require a “ZONE” selection.

4. Outdoor Air Temperature Sensor must be attached in all dual fuel

applications.

5. Dip switch No. 1 on Thermidistat should be set in OFF position for

air conditioner installations. This is factory default.

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

6. Dip switch No. 1 on Thermidistat should be set in ON position for

heat pump installations.

7. Dip switch No. 2 on Thermidistat should be set in OFF position for

single-speed compressor operation.

This is factory default.

8. Dip switch No. 2 on Thermidistat should be set in ON position for

two-speed compressor operation.

9. Configuration Option No. 10 “Dual Fuel Selection” must be turned

ON in all dual fuel applications.

10. NO connection should be made to the furnace HUM terminal when

using a Thermidistat.

11. Optional connection: If wire is connected, dip switch SW1-2 on

furnace control should be set in ON position

to allow Thermidistat/Thermostat to control furnace staging.

12. Optional connection: If wire is connected, ACRDJ jumper on

furnace control should be removed to

allow Thermidistat/Thermostat to control outdoor unit staging.

13. Furnace must control its own high-stage heating operation via

furnace control algorithm.

14. The RVS Sensing terminal “L” should not be connected. This is

internally used to sense defrost operation.

15. DO NOT SELECT the “FURNACE INTERFACE” or “BALANCE

POINT” option on the two-speed heat pump

control board. This is controlled internally by the

Thermidistat/Dual Fuel Thermostat.

16. Dip switch D on Dual Fuel Thermostat should be set in OFF

position for single-speed compressor operation.

This is factory default.

17. Dip switch D on Dual Fuel Thermostat should be set in ON position

for two-speed compressor operation.

A11617

Fig. 35 – Variable Speed Furnace Control for ECM Blower Motor

VENTING

The furnace shall be connected to a listed factory built chimney or vent,

or a clay-tile lined masonry or concrete chimney. Venting into an unlined

masonry chimney or concrete chimney is prohibited.

When an existing Category I furnace is removed or replaced, the original

venting system, may no longer be sized to properly vent the attached

appliances. An improperly sized Category I venting system could cause

the formation of condensate in the furnace and vent, leakage of

condensate and combustion products, and spillage of combustion

products into the living space.

Vent system or vent connectors may need to be resized. Vent systems or

vent connectors must be sized to approach minimum size as determined

using appropriate table found in the current edition of NFGC.

GENERAL VENTING REQUIREMENTS

Follow all safety codes for proper vent sizing and installation

requirements, including local building codes, the National Fuel Gas

Code NFPA 54/ANSI Z223.1 (NFGC), Parts 12 and 13 in the United

States, the local building codes, and furnace and vent manufacturers’

instructions.

These furnaces are design-certified as Category I furnaces in accordance

with ANSI Z21.47/CSA 2.3 and operate with a non-positive vent static

pressure to minimize the potential for vent gas leakage. Category I

furnaces operate with a flue loss not less than 17 percent to minimize the

potential for condensation in the venting system. These furnaces are

approved for common venting and multistory venting with other fan

assisted or draft hood equipped appliances in accordance with the

NFGC, the local building codes, and furnace and vent manufacturers’

instructions. The following information and warning must be considered

in addition to the requirements defined in the NFGC.

24-V THERMOSTAT

TERMINALS

PL2 – HOT SURFACE

IGNITER & INDUCER

MOTOR CONNECTOR

115-VAC (L2) NEUTRAL

CONNECTIONS

115-VAC (L1) LINE

VOLTAGE CONNECTIONS

EAC-1 TERMINAL

(115-VAC 1.0 AMP MAX.)

PL1 – LOW VOLTAGE MAIN

HARNESS CONNECTOR

TRANSFORMER 24-VAC

CONNECTIONS

3-AMP FUSE

STATUS AND COMM

LED LIGHTS

SW1 SETUP

SWITCHES AND

BLOWER OFF-

DELAY

MODEL PLUG

CONNECTOR

AIR CONDITIONING

(A/C) AIRFLOW

SETUP SWITCHES

COMMUNICATION

CONNECTOR

CONTINUOUS FAN

(CF) AIRFLOW

SETUP SWITCHES

OUTDOOR

AIR TEMP

CONNECTOR

HUMIDIFIER

TERMINAL (24-VAC

0.5 AMP MAX.

FLASH

UPGRADE

CONNECTOR

(FACTORY

ONLY)

SW4 SETUP

SWITCHES

SOFTWARE

VERSION

PART NUMBER AND

DATE CODE WWYY

ACRDJ – AIR

CONDITIONING

RELAY DISABLE

JUMPER

PL3 – ECM BLOWER

HARNESS

CONNECTOR

WARNING

CARBON MONOXIDE POISONING HAZARD

Failure to follow this warning could result in personal injury or death.

Do not bypass the draft safeguard switch, as an unsafe condition could

exist which must be corrected.

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

1. If a vent (common or dedicated) becomes blocked, the furnace will

be shut off by the draft safeguard switch located on the vent elbow.

2. Two-stage furnaces require Type B vent connectors outside the

casing in all configurations. Single wall vent connector may be

used inside the furnace casing with the transition to Type B vent

outside the furnace casing. Size the connector so that the FAN-Min

vent connector capacity is equal to or lower than the low fire rate of

the furnace and the FAN-Max vent connector capacity is equal to or

higher than the furnace high fire rate.

3. Do not vent this Category I furnace into a single wall dedicated or

common vent. The dedicated or common vent is considered to be

the vertical portion of the vent system that terminates outdoors.

4. Vent connectors serving Category I furnaces shall not be connected

into any portion of a mechanical draft system operating under

positive pressure.

5. Do not vent this appliance with any solid fuel burning appliance.

6. Category I furnaces must be vented vertically or nearly vertically

unless equipped with a listed mechanical venter. See SIDEWALL

VENTING section.

7. Do not vent this appliance into an unlined masonry chimney. (Refer

to Chimney Inspection Chart, Fig. 36.

Masonry Chimney Requirement

NOTE: These furnaces are CSA design-certified for use in exterior

tile-lined masonry chimneys with a factory accessory Chimney Adapter

Kit. Refer to the furnace rating plate for correct kit usage. The Chimney

Adapter Kits are for use with ONLY furnaces having a Chimney Adapter

Kit number marked on the furnace rating plate.

If a clay tile-lined masonry chimney is being used and it is exposed to

the outdoors below the roof line, relining might be required. Chimneys

shall conform to the Standard for Chimneys, Fireplaces, Vents, and Solid

Fuel Burning Appliances ANSI/NFPA 211 in the United States and must

be in good condition.

U.S.A. – Refer to Sections 13.1.8 and 13.2.20 of the NFPA 54/ANSI

Z223.1 or the authority having jurisdiction to determine whether relining

is required. If relining is required, use a properly sized listed metal liner,

Type-B vent, or a listed alternative venting design.

NOTE: See the NFPA 54/ANSI Z223.1 13.1.9 and 13.2.20 regarding

alternative venting design and the exception, which cover installations

such as our Chimney Adapter Kits which are listed for use with these

furnaces. See Product Data Sheet for accessory listing.

A10133

Fig. 36 – Chimney Inspection Chart

The Chimney Adapter Kit is a listed alternative venting system for these

furnaces. See the kit instructions for complete details.

This furnace is permitted to be vented into a clay tile-lined masonry

chimney that is exposed to the outdoors below the roof line, provided:

1. Vent connector is Type-B double-wall, and

2. This furnace is common vented with at least 1 draft hood equipped

appliance, and

3. The combined appliance input rating is less than the maximum

capacity given in Table 6, and

WARNING

CARBON MONOXIDE POISONING HAZARD

Failure to follow the steps outlined below for each appliance connected

to the venting system being placed into operation could result in carbon

monoxide poisoning or death.

The following steps shall be followed for each appliance connected to

the venting system being placed into operation, while all other

appliances connected to the venting system are not in operation:

1. Seal any unused openings in venting system.

2. Inspect the venting system for proper size and horizontal pitch, as

required in the National Fuel Gas Code, NFPA 54/ANSI Z223.1

and these instructions. Determine that there is no blockage or

restriction, leakage, corrosion and other deficiencies, which could

cause an unsafe condition.

3. As far as practical, close all building doors and windows and all

doors between the space in which the appliance(s) connected to

the venting system are located and other spaces of the building.

4. Close fireplace dampers.

5. Turn on clothes dryers and any appliance not connected to the

venting system. Turn on any exhaust fans, such as range hoods and

bathroom exhausts, so they are operating at maximum speed. Do

not operate a summer exhaust fan.

6. Follow the lighting instructions. Place the appliance being

inspected into operation. Adjust the thermostat so appliance is

operating continuously.

7. Test for spillage from draft hood equipped appliances at the draft

hood relief opening after 5 minutes of main burner operation. Use

the flame of a match or candle.

8. If improper venting is observed during any of the above tests, the

venting system must be corrected in accordance with the National

Fuel Gas Code, NFPA 54/ANSI Z223.1.

9. After it has been determined that each appliance connected to the

venting system properly vents when tested as outlined above,

return doors, windows, exhaust fans, fireplace dampers and any

other gas-fired burning appliance to their previous conditions of

use.

CHIMNEY INSPECTION CHART

For additional requirements refer to the National Fuel Gas Code NFPA 54/ANSI Z223.1 and ANSI/NFPA 211

Chimneys, Fireplaces, Vents, and Solid Fuel Burning Appliances

Consult

Par t C of

chimney adapter venting

instructions for

application

suitability

Is chimney

lined with properly

sized, listed liner or

Type-B vent?

Is chimney

to be dedicated to

a single

furnace?

Chimney

exposed to

outdoors below

roof line?

Repair

liner or top seal

or reline chimney as

necessary.

Mortar

or tile

debris?

Clay

tile misalignment,

missing sections,

gaps?

Debris

in cleanout?

Mortar, tile, metal vent,

fuel oil residue?

liner and top

seal in good

condition?

Is chimney

property lined with

clay tile liner?

Crown

condition:

Missing mortar

or brick?

Rebuild

crown.

Ye s

Reline

Ye s

Repair

Ye s

Remove mortar

and tile debris

Remove metal vent

or liner.

Ye s

Suitable

Not Suitable

Line chimney with property

sized, listed flexible metal

liner or Type-B vent per

NFGC

Vent

Sizing Tables and liner or

vent manufacturer’s

Installation instructions.

Install chimney

adapter per

instructions.

Chimney is

acceptable for use.

Install chimney

adapter per

instructions.

Consult

Par t B of

chimney adapter venting

instructions for

application

suitability.

Ye s

Not Suitable

Condensate

drainage at bottom

of chimney?

Ye s

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

4. The input rating of each space heating appliance is greater than the

minimum input rating given in Table 6 for the local 99% Winter

Design Temperature. Chimneys having internal areas greater than

38 sq. in. (24516 sq. mm) require furnace input ratings greater than

the input ratings of these furnaces. See footnote at bottom of

Table 6, and

5. The authority having jurisdiction approves.

If all of these conditions cannot be met, an alternative venting design

shall be used, such as the listed chimney adapter kit with a furnace listed

for use with the kit, a listed chimney-lining system, or a Type-B common

vent.

Inspections before the sale and at the time of installation will determine

the acceptability of the chimney or the need for repair and/or (re)lining.

Refer to Fig. 36 to perform a chimney inspection. If the inspection of a

previously used tile-lined chimney:

a. Shows signs of vent gas condensation, the chimney should be

relined in accordance with local codes and the authority having

jurisdiction. The chimney should be relined with a listed metal

liner, Type-B vent, or a listed chimney adapter kit shall be used to

reduce condensation. If a condensate drain is required by local

code, refer to the NFPA 54/ANSI Z223.1, Section 12.10 for

additional information on condensate drains.

b. Indicates the chimney exceeds the maximum permissible size in

the tables, the chimney should be rebuilt or relined to conform to

the requirements of the equipment being installed and the

authority having jurisdiction.

A chimney without a clay tile liner, which is otherwise in good

condition, shall be rebuilt to conform to ANSI/NFPA 211 or be lined

with a UL listed metal liner or UL listed Type-B vent. Relining with a

listed metal liner or Type-B vent is considered to be a vent-in-a-chase.

If a metal liner or Type-B vent is used to line a chimney, no other

appliance shall be vented into the annular space between the chimney

and the metal liner.

EXTERIOR MASONRY CHIMNEY FAN + NAT

INSTALLATIONS WITH TYPE-B DOUBLE-WALL

VENT CONNECTORS

NFPA & AGA

Appliance Application Requirements

Appliance operation has a significant impact on the performance of the

venting system. If the appliances are sized, installed, adjusted, and

operated properly, the venting system and/or the appliances should not

suffer from condensation and corrosion. The venting system and all

appliances shall be installed in accordance with applicable listings,

standards, and codes.

The furnace should be sized to provide 100 percent of the design heating

load requirement plus any margin that occurs because of furnace model

size capacity increments. Heating load estimates can be made using

approved methods available from Air Conditioning Contractors of

America (Manual J); American Society of Heating, Refrigerating, and

Air-Conditioning Engineers; or other approved engineering methods.

Excessive oversizing of the furnace could cause the furnace and/or vent

to fail prematurely.

When a metal vent or metal liner is used, the vent must be in good

condition and be installed in accordance with the vent manufacturer’s

instructions.

To prevent condensation in the furnace and vent system, the following

precautions must be observed:

1. The return-air temperature must be at least 60°F db except for brief

periods of time during warm-up from setback at no lower than 55°F

(13°C) db or during initial start-up from a standby condition.

2. Adjust the gas input rate per the installation instructions. Low gas

input rate causes low vent gas temperatures, causing condensation

and corrosion in the furnace and/or venting system. Derating is

permitted only for altitudes above 2000 Ft. (610 M).

3. Adjust the air temperature rise to the midpoint of the rise range or

slightly above. Low air temperature rise can cause low vent gas

temperature and potential for condensation problems.

4. Set the thermostat heat anticipator or cycle rate to reduce short

cycling.

Table 6 – Minimum Allowable Input Rating of

Space-Heating Appliance in Thousands of Btuh per Hour

VENT HEIGHT

FT. (M)

INTERNAL AREA OF CHIMNEY

SQ. IN. (SQ. MM)

(7741)

(12258)

18064)

(24516)

Local 99% Winter Design Temperature: 17 to 26 degrees F

*. The 99.6% heating (db) temperatures found in the 1997 or 2001 ASHRAE

Fundamentals Handbook, Climatic Design Information chapter, Table 1A

(United States) and 2A (Canada) or the 2005 ASHRAE Fundamentals

handbook, Climatic Design Information chapter, and the CD-ROM included

with the 2005 ASHRAE Fundamentals Handbook.

6 0 55 99 141

8 52 74 111 154

10 NR 90 125 169

15 NR NR 167 212

20 NR NR 212 258

30 NR NR NR 362

Local 99% Winter Design Temperature: 5 to 16 degrees F

6 NR 78 121 166

8 NR 94 135 182

10 NR 111 149 198

15 NR NR 193 247

20 NR NR NR 293

30 NR NR NR 377

Local 99% Winter Design Temperature: -10 to 4 degrees F

6 NR NR 145 196

8 NR NR 159 213

10 NR NR 175 231

15 NR NR NR 283

20 NR NR NR 333

30 NR NR NR NR

Local 99% Winter Design Temperature: -11 degrees F or

lower

Not recommended for any vent configuration.

Table 7 – Combined Appliance Maximum Input Rating

in Thousands of Btuh per Hour

VENT HEIGHT

FT (M)

INTERNAL AREA OF CHIMNEY

SQ. IN. (SQ. MM)

(7741)

(12258)

(18064)

(24516)

6 (1.8) 74 119 178 257

8 (2.4) 80 130 193 279

10 (3.0) 84 138 207 299

15 (4.5) NR 152 233 334

20 (6.0) NR NR 250 368

30 (9.1) NR NR NR 404

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

Air for combustion must not be contaminated by halogen compounds

which include chlorides, fluorides, bromides, and iodides. These

compounds are found in many common home products such as

detergent, paint, glue, aerosol spray, bleach, cleaning solvent, salt, and

air freshener, and can cause corrosion of furnaces and vents. Avoid using

such products in the combustion-air supply. Furnace use during

construction of the building could cause the furnace to be exposed to

halogen compounds, causing premature failure of the furnace or venting

system due to corrosion.

Vent dampers on any appliance connected to the common vent can cause

condensation and corrosion in the venting system. Do not use vent

dampers on appliances common vented with this furnace.

Additional Venting Requirements

A 4-in. (102 mm) round vent elbow is supplied with the furnace. A 5-in.

(127 mm) or 6- in. (152 mm) vent connector may be required for some

model furnaces. A field-supplied 4-in. (102 mm) to 5-in. (127 mm) or

4-in. (102 mm) to 6-in. (152 mm) sheet metal increaser fitting is required

when 5-in. (127 mm) or 6-in. (152 mm) vent connector is used. Refer to

Table 8 to determine the minimum vertical vent height for various

furnace and vent orientations. See Fig. 37 - Fig. 49 Venting Orientation

for approved vent configurations.

NOTE: Vent connector length for connector sizing starts at furnace vent

elbow. The 4-in. (102 mm) vent elbow is shipped for upflow

configuration and may be rotated for other positions. Remove the three

screws that secure vent elbow to furnace, rotate furnace vent elbow to

position desired, reinstall screws. The factory-supplied vent elbow does

NOT count as part of the number of vent connector elbows.

The vent connector can exit the furnace through one of five locations on

the casing.

1. Attach the single wall vent connector to the furnace vent elbow, and

fasten the vent connector to the vent elbow with at least two

field-supplied, corrosion-resistant, sheet metal screws located 180°

apart.

NOTE: An accessory flue extension is available to extend from the

furnace elbow to outside the furnace casing. SeeProduct Data Sheet for

accessory listing. If flue extension is used, fasten the flue extension to

the vent elbow with at least two field-supplied, corrosion-resistant, sheet

metal screws located 180° apart. Fasten the vent connector to the flue

extension with at least two field-supplied, corrosion resistant sheet metal

screws located 180° apart.

2. Vent the furnace with the appropriate connector, see

Fig. 37 - Fig. 49.)

3. Determine the correct location of the knockout to be removed.

4. Use a hammer and screwdriver to strike a sharp blow between the

tie points and work the slug back and forth until the slug breaks

free.

An accessory Vent Guard Kit is REQUIRED for downflow applications

for use where the vent exits through the lower portion of the furnace

casing. Refer to the Vent Guard Kit Instructions for complete details. See

Product Data Sheet for accessory listing.

The horizontal portion of the venting system shall slope upwards not less

than 1/4-in. per linear ft. (21 mm/m) from the furnace to the vent and

shall be rigidly supported every 5 ft. (1.5 M) or less with metal hangers

or straps to ensure there is no movement after installation.

Sidewall Venting

This furnace is not approved for direct sidewall horizontal venting.

Per section 12.4.3 of the NFPA 54/ANSI Z223.1, any listed mechanical

venter may be used, when approved by the authority having jurisdiction.

Select the listed mechanical venter to match the Btuh input of the

furnace being vented. Follow all manufacturer’s installation

requirements for venting and termination included with the listed

mechanical venter.

Caution!! For the following furnace and vent orientations, use the minimum vertical heights as specified in Table 8.

For all other orientations, follow exclusively the National Fuel Gas Code.

NOTE: All vent configurations must also meet National Fuel Gas Code venting requirements NFGC.

CAUTION

BURN HAZARD

Failure to follow this caution may result in personal injury.

Hot vent pipe is within reach of small children when installed in

downflow position.

See the following instruction.

CAUTION

CUT HAZARD

Failure to follow this caution may result in personal injury.

Sheet metal parts may have sharp edges or burrs. Use care and wear

appropriate protective clothing, safety glasses and gloves when

handling parts, and servicing furnaces.

Table 8 – Recommended Minimum Vent Height Per Furnace and Vent Orientation

FURNACE

ORIENTATION

VENT ORIENTATION

FURNACE INPUT

(BTUH/HR)

MIN. VENT

DIAMETER

IN. (mm)

*. 4-in. (102 mm) inside casing or vent guard

MIN. VERTICAL VENT

HEIGHT

FT. (M)

†

†. Including 4 in. (102 mm) vent section(s)

Downflow

Vent elbow left, then up

Fig. 42

132,000 & 110,000 5 (127) 12 (3.6)

Horizontal Left

Vent elbow right, then up

Fig. 45

132,000 5 (127) 7 (2.1)

Horizontal Left

Vent Elbow up

Fig. 46

132,000 5 (127) 7 (2.1)

Downflow

Vent elbow up then left

Fig. 38

110,000 5 (127) 10 (3.0)

Downflow

Vent elbow up, then right

Fig. 43

110,000 5 (127) 10 (3.0)

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

A03208

Fig. 37 – Upflow Application - Vent Elbow Up

A03210

Fig. 38 – Downflow Application - Vent Elbow Up then Left

A03209

Fig. 39 – Upflow Application - Vent Elbow Right

A03211

Fig. 40 – Downflow Application - Vent Elbow Up

A03213

Fig. 41 – Horizontal Left Application - Vent Elbow Left

A03207

Fig. 42 – Downflow Application - Vent Elbow Left then Up

SEE NOTES: 1,2,4,7,8,9

on the page following

these figures

SEE NOTES:1,2,3,4,5,7,8,9

on the page following

these figures

SEE NOTES: 1,2,3,4,7,8,9

on the pages following

these figures

SEE NOTES: 1,2,4,5,7,8,9

on the page following

these figures

SEE NOTES: 1,2,4,7,8,9 on the page

following these figures

SEE NOTES: 1,2,4,5,6,7,8,9

on the page following these figures

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

A03212

Fig. 43 – Downflow Application - Vent Elbow Up then Right

A03218

Fig. 44 – Horizontal Right Application-Vent Elbow Right

A03214

Fig. 45 – Horizontal Left Application - Vent Elbow Right then Up

A03215

Fig. 46 – Horizontal Left Application - Vent Elbow Up

A03216

Fig. 47 – Horizontal Left Application - Vent Elbow Right

A02068

Fig. 48 – Horizontal Right Application-Vent Elbow Left

A03219

Fig. 49 – Horizontal Right Application - Vent Elbow Left then Up

SEE NOTES:1,2,3,4,5,7,8,9

on the page following

these figures.

SEE NOTES: 1,2,4,7,8,9 on the page

following these figures

SEE NOTES: 1,2,4,5,7,8,9 on the page

following these figures

SEE NOTES: 1,2,4,5,7,8,9 on the page

following these figures

SEE NOTES: 1,2,4,5,7,8,9 on the page

following these figures

SEE NOTES: 1,2,4,5,7,8,9

SEE NOTES: 1,2,4,5,7,8,9 on the page

following these figures

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

Venting Notes for Fig. 37 - Fig. 49

1. For common vent, vent connector sizing and vent material: United States use the NFGC.

2. Immediately increase to 5-in. (102 mm) or 6-in. (152 mm) vent connector outside furnace casing when 5-in. (127 mm) vent connector is required,

refer to Note 1 above.

3. Side outlet vent for upflow and downflow installations must use Type B vent immediately after exiting the furnace, except when factory-approved

Downflow Vent Guard Kit is used in the downflow position. See Product Data Sheet for accessory listing.

4. Type-B vent where required, refer to Note 1 above.

5. A 4-in.(102 mm) single-wall (26 ga. min.) vent must be used inside furnace casing and when the factory-approved Downflow Vent Guard Kit is

used external to the furnace. See Product Data Sheet for accessory listing.

6. Accessory Downflow Vent Guard Kit required in downflow installations with lower vent configuration. See Product Data Sheet for accessory

listing.

7. Chimney Adapter Kit may be required for exterior masonry chimney applications. Refer to Chimney Adapter Kit for sizing and complete

application details. See Product Data Sheet for accessory listing.

8. Secure vent connector to furnace elbow with (2) corrosion-resistant sheet metal screws, spaced approximately 180° apart.

9. Secure all other single wall vent connector joints with (3) corrosion resistant screws spaced approximately 120° apart. Secure Type-B vent

connectors per vent connector manufacturer’s recommendations.

10. The total height of the vent and connector shall be at least seven feet for the 154,000 Btuh gas input rate model when installed in a downflow

application with furnace elbow turned to left side with the connector elbow outside furnace casing pointing upward, see Fig. 42.

START-UP, ADJUSTMENT, AND SAFETY

CHECK

GENERAL

1. Maintain 115-v wiring and ground. Improper polarity will result in

LED and no furnace operation.

2. Make thermostat wire connections at the 24-v terminal block on the

furnace control. Failure to make proper connections will result in

improper operation, see Fig. 24 - Fig. 35.

3. Gas supply pressure to the furnace must be greater than 4.5-In.

W.C. (0.16 psig) but not exceed 14-In. W.C. (0.5 psig).

4. Check all manual-reset switches for continuity.

5. Replace blower compartment door. Door must be in place to

operate furnace.

6. Setup switch descriptions The variable speed furnace control has

DIP switches to select thermostat staging, blower off delay timings,

air flow selection and other operational or service related functions,

see Fig. 35, Fig. 52 and Table 14.

START-UP PROCEDURES

1. Purge gas lines after all connections have been made.

2. Check gas lines for leaks.

3. To Begin Component Self-Test:

a. Remove Blower Access Door.

b. Disconnect the thermostat R lead from furnace control board.

c. Manually close blower door switch.

d. Turn Setup DIP switch SW1-6 ON, see Fig. 35, Fig. 56 and

Table 14.

NOTE: The furnace control allows all components, except the gas

valve, to be run for short period of time. This feature helps diagnose a

system problem in case of a component failure. Component test feature

will not operate if any thermostat signal is present at the control.

Refer to service label attached to furnace or see Fig. 52.

4. Component test sequence is as follows:

a. Inducer motor starts on high-speed and continues to run until

Step d. of component test sequence.

b. Hot surface igniter is energized for 15 sec., then off.

c. Blower motor operates for 15 sec.

d. Inducer motor goes to low-speed for 10 sec., then stops.

WARNING

FIRE HAZARD

Failure to follow this warning could result in personal injury, death or

property damage.

This furnace is equipped with manual reset limit switches in the gas

control area. The switches open and shut off power to the gas valve, if a

flame rollout or overheating condition occurs in the gas control area.

DO NOT bypass the switches. Correct problem before resetting the

switches.

CAUTION

CUT HAZARD

Failure to follow this caution may result in personal injury.

Sheet metal parts may have sharp edges or burrs. Use care and wear

appropriate protective clothing, safety glasses and gloves when

handling parts, and servicing furnaces.

WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal injury, death,

and/or property damage.

Never purge a gas line into a combustion chamber. Never test for gas

leaks with an open flame. Use a commercially available soap solution

made specifically for the detection of leaks to check all connections. A

fire or explosion may result causing property damage, personal injury

or loss of life.

WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury, or death.

Blower access door switch opens 115-v power to control. No

component operation can occur unless switch is closed. Caution must

be taken when manually closing this switch for service purposes.

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

e. After component test is completed, one or more status codes (11,

25 or 41) will flash. See component test section of service label

(Fig. 52) in furnace for explanation of status codes.

NOTE: To repeat component test, turn setup switch SW1-6 OFF, then

back ON.

5. Turn setup DIP switch SW1-6 OFF. Reconnect R lead to furnace

control board, release blower door switch and reinstall blower

access door.

6. Operate furnace per instruction on inner door.

7. Verify furnace shut down by lowering thermostat setting below

room temperature.

8. Verify furnace restarts by raising thermostat setting above room

temperature.

ADJUSTMENTS

A93059

Fig. 50 – Orifice Hole

Furnace gas input rate on rating plate is for installations at altitudes up to

2000 Ft. (610 M). Furnace input rate must be within +/-2 percent of

furnace rating plate input. For altitudes above 5500 Ft. (1676 M), a

field-supplied high altitude pressure switch is required. Perform the

following steps:

1. Determine the correct gas input rate.

The input rating for altitudes above 2,000 ft. (610 M) must be

reduced by 4 percent for each 1,000 ft. (305 M) above sea level.

For installations below 2000 Ft. (610 M), refer to the unit rating

plate. For installations above 2000 Ft. (610 M), multiply the input

on the rating plate by the de-rate multiplier in Table 9 for the

correct input rate.

2. Determine the correct orifice and manifold pressure adjustment. All

models in all positions except Low NOx models in downflow and

horizontal positions use Table 15 (22,000 Btuh per burner.) Low

NOx models in downflow or horizontal positions must use Table 16

(21,000 Btuh per burner.) See input listed on rating plate.

a. Obtain average yearly gas heat value (at installed altitude) from

local gas supplier.

b. Obtain average yearly gas specific gravity from local gas

supplier.

c. Find installation altitude in Table 15 or Table 16.

d. Find closest natural gas heat value and specific gravity in

Table 15 or Table 16.

e. Follow heat value and specific gravity lines to point of

intersection to find orifice size and low-and high-heat manifold

pressure settings for proper operation.

f. Check and verify burner orifice size in furnace. NEVER

ASSUME ORIFICE SIZE. ALWAYS CHECK AND VERIFY.

NOTE: If orifice hole appears damaged or it is suspected to have been

redrilled, check orifice hole with a numbered drill bit of correct size.

Never redrill an orifice. A burr-free and squarely aligned orifice hole is

essential for proper flame characteristics.

g. Replace orifice with correct size, if required by Table 15 or

Table 16. Use only factory-supplied orifices. See Example

below.

3. Adjust manifold pressure to obtain low fire input rate, see Fig. 21.

a. Turn gas valve ON/OFF switch to OFF.

b. Remove manifold pressure tap plug from gas valve.

c. Connect a water column manometer or similar device to

manifold pressure tap.

d. Turn gas valve ON/OFF switch to ON.

e. Move setup SW1-2 on furnace control to ON position to lock

furnace in low-heat operation, see Table 14 and Fig. 35.

f. Manually close blower door switch.

g. Jumper R and W/W1 thermostat connections on control to start

furnace, see Fig. 35.

WARNING

FIRE HAZARD

Failure to follow this warning could result in personal injury, death

and/or property damage.

DO NOT bottom out gas valve regulator adjusting screw. This can

result in unregulated manifold pressure and result in excess overfire and

heat exchanger failures.

CAUTION

FURNACE DAMAGE HAZARD

Failure to follow this caution may result in reduced furnace life.

DO NOT redrill orifices. Improper drilling (burrs, out-of-round holes,

etc.) can cause excessive burner noise and misdirection of burner

flames. This can result in flame impingement of heat exchangers,

causing failures, see Fig. 50.

BURNER

ORIFICE

EXAMPLE: 0–2000 ft. (0-610 M) altitude

For 22,000 Btuh per burner application use Table 15.

Heating value = 1000 Btuh/cu ft.

Specific gravity = 0.62

Therefore: Orifice No. 43*

Manifold pressure: 3.7-In. W.C. for high-heat

1.6-In. W.C. for low-heat

* Furnace is shipped with No. 43 orifices. In this example all main burner orifices are the

correct size and do not need to be changed to obtain proper input rate.

Table 9 – Altitude Derate Multiplier for U.S.A.

ALTITUDE

FT. (M)

PERCENT

OF DERATE

DERATE MULTIPLIER

FACTOR*

0–2000

(0-610)

0 1.00

2001–3000

(610-914)

8–12 0.90

3001–4000

(914-1219)

12–16 0.86

4001–5000

(1219-1524)

16–20 0.82

5001–6000

1524-1829)

20–24 0.78

6001–7000

(1829-2134)

24–28 0.74

7001–8000

(2134-2438)

28–32 0.70

8001–9000

(2438-2743)

32–36 0.66

9001–10,000

(2743-3048)

36–40 0.62

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

h. Remove regulator adjustment cap from low heat gas valve

pressure regulator (see Fig. 21) and turn low-heat adjusting

screw (3/16 or smaller flat-tipped screwdriver) counterclockwise

(out) to decrease input rate or clockwise (in) to increase input

rate.

NOTE: DO NOT set low-heat manifold pressure less than 1.4-In. W.C.

or more than 1.7-In. W.C. for natural gas. If manifold pressure is outside

this range, change main burner orifices.

i. Install low-heat regulator adjustment cap.

j. Move setup switch SW1-2 to off position after completing

low-heat adjustment.

k. Leave manometer or similar device connected and proceed to

Step 4.

4. Adjust manifold pressure to obtain high fire input rate, see Fig. 21.

a. Jumper R to W/W1 and W2 thermostat connections on furnace

control. This keeps furnace locked in high-heat operation.

b. Remove regulator adjustment cap from high-heat gas valve

pressure regulator, see Fig. 21, and turn high heat adjusting screw

(3/16-in. or smaller flat-tipped screwdriver) counterclockwise

(out) to decrease input rate or clockwise (in) to increase input

rate.

NOTE: DO NOT set high-heat manifold pressure less than 3.2-In. W.C.

or more than 3.8 In. W.C. for natural gas. If manifold pressure is outside

this range, change main burner orifices to obtain manifold pressure in

this range.

c. When correct input is obtained, replace caps that conceal gas

valve regulator adjustment screws. Main burner flame should be

clear blue, almost transparent.

d. Remove jumpers R to W/W1 and R to W2.

5. Verify natural gas input rate by clocking meter.

NOTE: Gas valve regulator adjustment caps must be in place for proper

input to be clocked.

a. Turn off all other gas appliances and pilots served by the meter.

b. Move setup switch SW1-2 to ON position. This keeps furnace

locked in low-heat operation.

c. Jumper R to W/W1.

d. Run furnace for 3 minutes in low-heat operation.

e. Measure time (in sec) for gas meter to complete 1 revolution and

note reading. The 2 or 5 cubic feet dial provides a more accurate

measurement of gas flow.

f. Refer to Table 10 for cubic ft. of gas per hr.

g. Multiply gas rate cu ft./hr by heating value (Btuh/cu ft.) to obtain

input. If clocked rate does not match required input from Step 1,

increase manifold pressure to increase input or decrease manifold

pressure to decrease input. Repeat steps d through g until correct

low-heat input is achieved. Re-install low heat regulator seal cap

on gas valve.

h. Move setup switch SW1-2 to OFF position and jumper R to

W/W1, and W2. This keeps furnace locked in high-heat

operation. Repeat items d through g for high-heat operation.

6. Set Temperature Rise.

NOTE: Blower access door must be installed when taking temperature

rise reading. Leaving blower access door off will result in incorrect

temperature measurements.

When setup switch SW1-4 is ON, operation will be near the high end of

the rise range for improved comfort.

Furnace must operate within ranges of temperature rise specified on the

furnace rating plate. Determine air temperature rise as follows:

a. Place thermometers in return and supply ducts as near furnace as

possible. Be sure thermometers do not see heat exchanger so that

radiant heat does not affect readings. This practice is particularly

important with straight-run ducts.

b. When thermometer readings stabilize, subtract return-air

temperature from supply-air temperature to determine air

temperature rise.

NOTE: Temperature rise can be determined for low-heat operation by

placing setup switch SW1-2 on furnace control in ON position and

jumping R to W/W1. For high-heat operation, place setup switch SW1-2

in OFF position and jumper R to W1 and R-W2 on furnace control. DO

CAUTION

FURNACE DAMAGE HAZARD

Failure to follow this caution may result in shorten furnace life.

Set air temperature rise within limits specified on the rating plate to

prevent reduced life of furnace components. Operation is within a few

degrees of the mid-point of rise range when setup switch SW1-4 is

OFF.

CAUTION

UNIT DAMAGE HAZARD

Failure to follow this caution may result in overheating the heat

exchangers or condensing flue gases in heat exchanger areas not

designed for condensate.

Temperature rise must be within limits specified on unit rating plate.

Operation is within a few degrees of midpoint of rise range when setup

switch SW1-4 is OFF.

Table 10 – Gas Rate (CU ft./hr)

SEC.

FOR 1 REV.

SIZE OF TEST DIAL

SEC. FOR

1 REV.

SIZE OF TEST DIAL

1 Cu

Ft.

2 Cu

Ft.

5 Cu

Ft.

1 Cu

Ft.

2 Cu

Ft.

5 Cu

Ft.

10 360 720 1800 50 72 144 360

11 327 655 1636 51 71 141 355

12 300 600 1500 52 69 138 346

13 277 555 1385 53 68 136 340

14 257 514 1286 54 67 133 333

15 240 480 1200 55 65 131 327

16 225 450 1125 56 64 129 321

17 212 424 1059 57 63 126 316

18 200 400 1000 58 62 124 310

19 189 379 947 59 61 122 305

20 180 360 900 60 60 120 300

21 171 343 857 62 58 116 290

22 164 327 818 64 56 112 281

23 157 313 783 66 54 109 273

24 150 300 750 68 53 106 265

25 144 288 720 70 51 103 257

26 138 277 692 72 50 100 250

27 133 267 667 74 48 97 243

28 129 257 643 76 47 95 237

29 124 248 621 78 46 92 231

30 120 240 600 80 45 90 225

31 116 232 581 82 44 88 220

32 113 225 563 84 43 86 214

33 109 218 545 86 42 84 209

34 106 212 529 88 41 82 205

35 103 206 514 90 40 80 200

36 100 200 500 92 39 78 196

37 97 195 486 94 38 76 192

38 95 189 474 96 38 75 188

39 92 185 462 98 37 74 184

40 90 180 450 100 36 72 180

41 88 176 439 102 35 71 178

42 86 172 429 104 35 69 173

43 84 167 419 106 34 68 170

44 82 164 409 108 33 67 167

45 80 160 400 110 33 65 164

46 78 157 391 112 32 64 161

47 76 153 383 116 31 62 155

48 75 150 375 120 30 60 150

49 73 147 367

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

NOT forget to return setup switch to OFF position and remove jumper

upon completion of testing.

c. This furnace is capable of automatically providing proper airflow

to maintain the temperature rise within the range specified on

furnace rating plate. If temperature rise is outside this range,

proceed as follows:

(1.) Check gas input for low- and high-heat operation.

(2.) Check derate for altitude if applicable.

(3.) Check all return and supply ducts for excessive restrictions

causing static pressure greater than 0.5-In. W.C.

(4.) Ensure setup switch SW1-4 (Comfort/Efficiency) is in

OFF=Efficiency position when a bypass humidifier is used,

see Fig. 35 for switch location.)

(5.) Make sure proper model plug is installed.

d. Remove thermostat jumpers and release blower access door

switch.

e. Repeat Steps a through c as required to adjust for high heat

temperature rise.

f. When correct high heat input rate and temperature rise is

achieved, turn gas valve ON/OFF switch to OFF.

g. Release blower access door switch.

h. Remove manometer or similar device from gas valve.

i. Re-install manifold pressure tap plug in gas valve, see Fig. 21.

j. Remove thermostat jumper wire from furnace control board.

k. Turn gas valve ON/OFF switch to ON.

l. Proceed to Step 7, “Set Blower Off Delay” before installing

blower access door.

7. Set Blower Off Delay

a. Remove blower access door if installed.

b. Turn Dip switch SW-7 or SW-8 ON or OFF for desired blower

off delay, see Table 11, Table 14, and Fig. 35 and Fig. 56.

8. Set thermostat heat anticipator.

a. Mechanical thermostat. Set thermostat heat anticipator to match

the amp. draw of the electrical components in the R-W/W1

circuit. Accurate amp. draw readings can be obtained at the wires

normally connected to thermostat subbase terminals, R and W.

The thermostat anticipator should NOT be in the circuit while

measuring current.

(1.) Set SW1-2 switch on furnace control board to ON.

(2.) Remove thermostat from subbase or from wall.

(3.) Connect an amp. meter across the R and W subbase

terminals or R and W wires at wall, see Fig. 51.

(4.) Record amp. draw across terminals when furnace is in low

heat and after blower starts.

(5.) Set heat anticipator on thermostat per thermostat

instructions and install on subbase or wall.

(6.) Turn SW1-2 switch OFF.

(7.) Install blower access door.

b. Electronic thermostat: Set cycle rate for 3 cycles per hr.

9. Set Airflow for Air Conditioning -Single Stage and High Stage

Cooling

The ECM blower can be adjusted for a range of airflow for Low

Speed or High Speed cooling. See Table 13-Air Delivery - CFM

(With Filter). Depending on the model size, the cooling airflow can

be adjusted from 1.5 to 6 tons based on 350 CFM/ton. Refer to

Table 12.

The cooling airflow is adjusted by turning Setup switches SW2-1,

SW2-2 and SW2-3 either ON or OFF. Select the required airflow,

see Fig. 14. Fig. 14 is based on 350 CFM per ton. For airflow at 400

CFM per ton, turn Setup SW1-5 ON, see Table 11, Table 14,

Fig. 35, and Fig. 56.

A96316

Fig. 51 – Amp. Draw Check with Ammeter

NOTE: 5.5 ton airflow will truncate at 2200 cfm on applicable models.

For a complete explanation of cooling airflow, refer to the section titled

“Sequence of Operation.”

10. Set Airflow For Continuous Fan/Low Speed Cooling Airflow The

ECM blower motor can be adjusted for continuous fan speeds

different than heating or cooling fan speed. See Table 13 - Air

Delivery - CFM (With Filter). Select the required continuous fan

airflow, see Fig. 14.

The continuous fan speed is also the switch setting for low speed

cooling when furnace is used with a 2-speed cooling unit. Adjust

the Continuous Fan CFM to match the airflow required for low

speed cooling. Select the required airflow, see Fig. 53. For airflow

at 400 CFM per ton, turn Setup SW1-5 ON, see Fig. 14. The

airflow selected for low speed cooling will also be the airflow used

for continuous fan.

The continuous fan speed can be further adjusted at the thermostat

using the “Comfort Fan” select function. Changing the continuous

fan speed at the thermostat DOES NOT change the low speed

cooling airflow selected at the control board.

WARNING

FIRE HAZARD

Failure to follow this warning could result in personal injury, death,

and/or property damage.

Reinstall manifold pressure tap plug in gas valve to prevent gas leak.

CAUTION

FURNACE OVERHEATING HAZARD

Failure to follow this caution may result in reduced furnace life.

Recheck temperature rise. It must be within limits specified on the

rating plate. Recommended operation is at the mid-point of rise range

or slightly above.

Table 11 – Blower Off Delay Setup Switch

DESIRED HEATING MODE

BLOWER OFF DELAY (SEC.)

SETUP SWITCH

(SW-7 AND -8)

POSITION

SW1-7 SW1-8

90 OFF OFF

120 ON OFF

150 OFF ON

180 ON ON

R Y W G

10 TURNS

THERMOSTAT SUBBASE

TERMINALS WITH

THERMOSTAT REMOVED

(ANITICIPATOR, CLOCK, ETC.,

MUST BE OUT OF CIRCUIT.)

HOOK-AROUND

AMMETER

EXAMPLE:

5.0 AMPS ON AMMETER

10 TURNS AROUND JAWS

0.5 AMPS FOR THERMOSTAT

ANTICIPATOR SETTING

FROM UNIT 24-V

CONTROL TERMINALS

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

Check Safety Controls

The flame sensor, gas valve, and pressure switch were all checked in the

Start-up procedure section as part of normal operation.

1. Check Main Limit Switch

This control shuts off combustion system and energizes

air-circulating blower motor, if furnace overheats. By using this

method to check limit control, it can be established that limit is

functioning properly and will operate if there is a restricted

return-air supply or motor failure. If limit control does not function

during this test, cause must be determined and corrected.

a. Run furnace for at least 5 minutes.

b. Gradually block off return air with a piece of cardboard or sheet

metal until the limit trips.

c. Unblock return air to permit normal circulation.

d. Burners will re-light when furnace cools down.

2. Check draft safeguard switch. The purpose of this control is to

cause the safe shutdown of the furnace during certain blocked vent

conditions.

a. Verify vent pipe is cool to the touch.

b. Disconnect power to furnace and remove vent connector from

furnace vent elbow.

c. Restore power to furnace and set room thermostat above room

temperature.

d. After normal start-up, allow furnace to operate for 2 minutes,

then block vent elbow in furnace 80 percent of vent area with a

piece of flat sheet metal.

e. Furnace should cycle off within 2 minutes. If gas does not shut

off within 2 minutes, determine reason draft safeguard switch did

not function properly and correct condition.

NOTE: Should switch remain open longer than 3 minutes, furnace

control board will lockout the furnace for 3 hours. To reset furnace

control board, turn thermostat below room temperature or from HEAT to

OFF and turn 115-v power OFF, then back ON.

f. Remove blockage from furnace vent elbow.

g. Switch will auto-reset when it cools.

h. Re-install vent connector.

3. Check Pressure Switch(es)

This control proves operation of the draft inducer blower.

a. Turn off 115-v power to furnace.

b. Disconnect inducer motor lead wires from wire harness.

c. Turn on 115-v power to furnace.

d. Set thermostat to “call for heat” and wait 1 minute. When

pressure switch is functioning properly, hot surface igniter

should NOT glow and control diagnostic light flashes a status

code 32. If hot surface igniter glows when inducer motor is

disconnected, shut down furnace immediately.

e. Determine reason pressure switch did not function properly and

correct condition.

f. Turn off 115-v power to furnace.

g. Reconnect inducer motor wires, replace outer door, and turn on

115-v power.

h. Blower will run for 90 seconds before beginning the call for heat

again.

i. Furnace should ignite normally.

Checklist

1. Put away tools and instruments. Clean up debris.

2. Verify that switches SW1-1 and SW1-6 are OFF and other setup

switches are set as desired. Verify that switches SW1-7 and SW1-8

for the blower OFF DELAY are set as desired per Table 14.

3. Verify that blower and burner access doors are properly installed.

4. Cycle test furnace with room thermostat.

5. Check operation of accessories per manufacturer’s instructions.

6. Review User’s Guide with owner.

7. Attach literature packet to furnace.

X- Indicated an allowable selection.

Table 12 – Cooling Airflow Adjustments from 1.5 to 6 Tons

AIR CONDITIONING TONS

(12,000 BTU/HR)

AIRFLOW (CFM) 070 MODEL 090 MODEL 110 & 135 MODELS

1-1/2 525

X —

2 700 X

2-1/2 875 X X

3 1050

X X

3-1/2 1225 X

4 1400 — X X

5 1750 — —

6 2100 — — X

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

Table 13 – Air Delivery - CFM (With Filter)

(SW1-5 and SW4-3 set to OFF, except as indicated. See Footnotes

and

)

Unit Size:36045C17 Clg/CF Switch Settings External Static Pressure (ESP)

Clg Switches SW2-3 SW2-2 SW2-1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Clg Default: OFF OFF OFF 1070 1080 1085 1095 1095 1100 1095 1090 1080 1070

CF Switches SW3-3 SW3-2 SW3-1

Low-Clg Default: OFF OFF OFF 525 540 540 550 550

See Note

Cooling Airflow

(SW2)

Low-Cooling Airflow

(SW3)

OFF OFF ON 525 540 540 550 550

See Note

OFF ON OFF 700 720 715 730 735 745 745 745 735 725

OFF ON ON 885 905 920 925 920 910 905 900 895 885

ON OFF OFF 1070 1080 1085 1095 1095 1100 1095 1090 1080 1070

ON OFF ON 1250 1265 1275 1280 1275 1265 1255 1240 1205 1170

ON ON OFF 1425 1425 1410 1380 1340 1305 1270 1235 1200 1165

ON ON ON 1425 1425 1410 1380 1340 1305 1270 1235 1200 1165

Maximum Clg Airflow

1480 1445 1415 1380 1345 1310 1275 1235 1200 1165

CF Switches SW3-3 SW3-2 SW3-1

Cont. Fan Default: OFF OFF OFF 525 540 540 550 550

See Note

Continuous Fan

Airflow (SW3)

OFF OFF ON 525 540 540 550 550

See Note

OFF ON OFF 700 720 715 730 735 745 745 745 735 725

OFF ON ON 885 905 920 925 920 910 905 900 895 885

ON OFF OFF 1070 1080 1085 1095 1095 1100 1095 1090 1080 1070

ON OFF ON 1070 1080 1085 1095 1095 1100 1095 1090 1080 1070

ON ON OFF 1070 1080 1085 1095 1095 1100 1095 1090 1080 1070

ON ON ON 1070 1080 1085 1095 1095 1100 1095 1090 1080 1070

Heating (SW1)

High Heat Airflow

730 730 735 750 765 770 770 770 760 750

Low Heat Airflow

605 625 635 630 635 635 630 625 615 605

Unit Size: 36070C14 Clg/CF Switch Settings External Static Pressure (ESP)

Clg Switches SW2-3 SW2-2 SW2-1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Clg Default: OFF OFF OFF 1050 1050 1050 1050 1050 1050 1045 1035 1020 1000

CF Switches SW3-3 SW3-2 SW3-1

Low-Clg Default: OFF OFF OFF 515 500 500 490 485

See Note

Cooling Airflow

(SW2)

Low-Cooling Airflow

(SW3)

OFF OFF ON 515 500 500 490 485

See Note

OFF ON OFF 690 680 675 680 675

See Note

OFF ON ON 875 875 875 870 865 855 850 835 825 820

ON OFF OFF 1050 1050 1050 1050 1050 1050 1045 1035 1020 1000

ON OFF ON 1220 1225 1225 1225 1225 1220 1205 1190 1185 1170

ON ON OFF 1220 1225 1225 1225 1225 1220 1205 1190 1185 1170

ON ON ON 1220 1225 1225 1225 1225 1220 1205 1190 1185 1170

Maximum Clg Airflow

1395 1400 1400 1400 1395 1385 1370 1340 1300 1245

CF Switches SW3-3 SW3-2 SW3-1

Cont. Fan Default: OFF OFF OFF 515 500 500 490 485

See Note

Continuous Fan

Airflow (SW3)

OFF OFF ON 515 500 500 490 485

See Note

OFF ON OFF 690 680 675 680 675

See Note

OFF ON ON 875 875 875 870 865 855 850 835 825 820

ON OFF OFF 1050 1050 1050 1050 1050 1050 1045 1035 1020 1000

ON OFF ON 1220 1225 1225 1225 1225 1220 1205 1190 1185 1170

ON ON OFF 1220 1225 1225 1225 1225 1220 1205 1190 1185 1170

ON ON ON 1220 1225 1225 1225 1225 1220 1205 1190 1185 1170

Heating (SW1)

High Heat Airflow

1160 1165 1175 1180 1180 1180 1180 1180 1180 1175

Low Heat Airflow

735 735 735 735 725

See Note

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

(SW1-5 and SW4-3 set to OFF, except as indicated. See Footnotes

and

)

Unit Size: 48070C17 Clg/CF Switch Settings External Static Pressure (ESP)

Clg Switches SW2-3 SW2-2 SW2-1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Clg Default: OFF OFF OFF 1435 1435 1435 1420 1380 1345 1310 1270 1235 1200

CF Switches SW3-3 SW3-2 SW3-1

Low-Clg Default: OFF OFF OFF 705 715 720 720 715 705 700 690 680 665

Cooling Airflow

(SW2)

Low-Cooling Airflow

(SW3)

OFF OFF ON 530 535 530 520 505

See Note

OFF ON OFF 705 715 720 720 715 705 700 690 680 665

OFF ON ON 870 885 890 895 895 895 890 885 875 865

ON OFF OFF 1110 1110 1110 1105 1100 1090 1085 1075 1065 1050

ON OFF ON 1240 1240 1245 1245 1240 1235 1230 1225 1215 1210

ON ON OFF 1435 1435 1435 1420 1380 1345 1310 1270 1235 1200

ON ON ON 1435 1435 1435 1420 1380 1345 1310 1270 1235 1200

Maximum Clg Airflow

1510 1480 1445 1410 1375 1340 1305 1270 1235 1200

CF Switches SW3-3 SW3-2 SW3-1

Cont. Fan Default: OFF OFF OFF 805 800 795 790 775 765 750 735 715 700

Continuous Fan

Airflow (SW3)

OFF OFF ON 520 520 515 510 495

See Note

OFF ON OFF 635 630 625 620 605 595 580 565 550 535

OFF ON ON 805 800 795 790 775 765 750 735 715 700

ON OFF OFF 805 800 795 790 775 765 750 735 715 700

ON OFF ON 805 800 795 790 775 765 750 735 715 700

ON ON OFF 805 800 795 790 775 765 750 735 715 700

ON ON ON 805 800 795 790 775 765 750 735 715 700

Heating (SW1)

High Heat Airflow

1245 1250 1250 1240 1235 1230 1225 1215 1205 1200

Low Heat Airflow

1040 1040 1035 1030 1030 1020 1010 1000 990 980

Unit Size: 60070C21 Clg/CF Switch Settings External Static Pressure (ESP)

Clg Switches SW2-3 SW2-2 SW2-1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Clg Default: OFF OFF OFF 1785 1815 1825 1825 1825 1820 1810 1805 1795 1755

CF Switches SW3-3 SW3-2 SW3-1

Low-Clg Default: OFF OFF OFF 855 905 925 950 970 970 960 955 970 965

Cooling Airflow

(SW2)

Low-Cooling Airflow

(SW3)

OFF OFF ON 670 735 765 775 790

See Note

OFF ON OFF 855 905 925 950 970 970 960 955 970 965

OFF ON ON 1040 1040 1050 1085 1085 1095 1100 1090 1080 1090

ON OFF OFF 1235 1255 1290 1300 1315 1310 1310 1310 1295 1285

ON OFF ON 1495 1475 1490 1490 1495 1490 1485 1470 1460 1455

ON ON OFF 1785 1815 1825 1825 1825 1820 1810 1805 1795 1755

ON ON ON 2145 2140 2135 2125 2110 2090 2040 1965 1875 1800

Maximum Clg Airflow

2225 2215 2205 2190 2150 2110 2045 1970 1880 1800

CF Switches SW3-3 SW3-2 SW3-1

Cont. Fan Default: OFF OFF OFF 855 905 925 950 970 970 960 955 970 965

Continuous Fan

Airflow (SW3)

OFF OFF ON 670 735 765 775 790

See Note

OFF ON OFF 855 905 925 950 970 970 960 955 970 965

OFF ON ON 1040 1040 1050 1085 1085 1095 1100 1090 1080 1090

ON OFF OFF 1040 1040 1050 1085 1085 1095 1100 1090 1080 1090

ON OFF ON 1040 1040 1050 1085 1085 1095 1100 1090 1080 1090

ON ON OFF 1040 1040 1050 1085 1085 1095 1100 1090 1080 1090

ON ON ON 1040 1040 1050 1085 1085 1095 1100 1090 1080 1090

Heating (SW1)

High Heat Airflow

1195 1215 1240 1250 1255 1270 1265 1260 1255 1245

Low Heat Airflow

1085 1090 1115 1135 1160 1160 1155 1150 1150 1140

Table 13 – Air Delivery - CFM (With Filter) (Continued)

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

(SW1-5 and SW4-3 set to OFF, except as indicated. See Footnotes

and

)

Unit Size: 48090C17 Clg/CF Switch Settings External Static Pressure (ESP)

Clg Switches SW2-3 SW2-2 SW2-1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Clg Default: OFF OFF OFF 1350 1370 1390 1390 1400 1390 1380 1380 1360 1340

CF Switches SW3-3 SW3-2 SW3-1

Low-Clg Default: OFF OFF OFF 680 680 680 675 670

See Note

Cooling Airflow

(SW2)

Low-Cooling Airflow

(SW3)

OFF OFF ON 525 520 525 495 475

See Note

OFF ON OFF 680 680 680 675 670

See Note

OFF ON ON 815 845 845 855 850 850 845 835 820 805

ON OFF OFF 1005 1005 1015 1035 1040 1040 1035 1030 1025 1010

ON OFF ON 1190 1200 1200 1205 1205 1215 1205 1200 1185 1170

ON ON OFF 1350 1370 1390 1390 1400 1390 1380 1380 1360 1340

ON ON ON 1350 1370 1390 1390 1400 1390 1380 1380 1360 1340

Maximum Clg Airflow

1595 1600 1600 1600 1595 1555 1505 1465 1430 1390

CF Switches SW3-3 SW3-2 SW3-1

Cont. Fan Default: OFF OFF OFF 680 680 680 675 670

See Note

Continuous Fan

Airflow (SW3)

OFF OFF ON 525 520 525 495 475

See Note

OFF ON OFF 680 680 680 675 670

See Note

OFF ON ON 815 845 845 855 850 850 845 835 820 805

ON OFF OFF 1005 1005 1015 1035 1040 1040 1035 1030 1025 1010

ON OFF ON 1190 1200 1200 1205 1205 1215 1205 1200 1185 1170

ON ON OFF 1190 1200 1200 1205 1205 1215 1205 1200 1185 1170

ON ON ON 1190 1200 1200 1205 1205 1215 1205 1200 1185 1170

Heating (SW1)

High Heat Airflow

1190 1205 1210 1210 1210 1210 1210 1210 1210 1200

Low Heat Airflow

950 970 985 985 985 985 985 985 985 980

Unit Size: 60090C21 Clg/CF Switch Settings External Static Pressure (ESP)

Clg Switches SW2-3 SW2-2 SW2-1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Clg Default: OFF OFF OFF 1785 1805 1815 1835 1840 1855 1860 1850 1845 1835

CF Switches SW3-3 SW3-2 SW3-1

Low-Clg Default: OFF OFF OFF 925 935 945 960 980 965 940 925 920 900

Cooling Airflow

(SW2)

Low-Cooling Airflow

(SW3)

OFF OFF ON 715 715 735 730 730

See Note

OFF ON OFF 925 935 945 960 980 965 940 925 920 900

OFF ON ON 1040 1045 1030 1055 1060 1045 1060 1045 1030 1005

ON OFF OFF 1295 1320 1285 1335 1350 1340 1350 1335 1310 1300

ON OFF ON 1505 1525 1480 1480 1490 1475 1465 1455 1450 1445

ON ON OFF 1785 1805 1815 1835 1840 1855 1860 1850 1845 1835

ON ON ON 2250 2265 2270 2265 2255 2245 2220 2175 2120 2060

Maximum Clg Airflow

2375 2375 2375 2365 2330 2285 2235 2185 2140 2075

CF Switches SW3-3 SW3-2 SW3-1

Cont. Fan Default: OFF OFF OFF 925 935 945 960 980 965 940 925 920 900

Continuous Fan

Airflow (SW3)

OFF OFF ON 715 715 735 730 730

See Note

OFF ON OFF 925 935 945 960 980 965 940 925 920 900

OFF ON ON 1040 1045 1030 1055 1060 1045 1060 1045 1030 1005

ON OFF OFF 1295 1320 1285 1335 1350 1340 1350 1335 1310 1300

ON OFF ON 1505 1525 1480 1480 1490 1475 1465 1455 1450 1445

ON ON OFF 1505 1525 1480 1480 1490 1475 1465 1455 1450 1445

ON ON ON 1505 1525 1480 1480 1490 1475 1465 1455 1450 1445

Heating (SW1)

High Heat Airflow

1590 1610 1605 1605 1600 1605 1610 1610 1615 1620

Low Heat Airflow

1425 1450 1440 1465 1470 1455 1450 1440 1435 1430

Table 13 – Air Delivery - CFM (With Filter) (Continued)

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

1. Nominal 350 CFM/ton cooling airflow is delivered with SW1-5 and SW4-3 set to OFF.

Set SW1-5 to ON for nominal 400 CFM/ton (+15% airflow).

Set SW4-3 to ON for nominal 325 CFM/ton (-7% airflow).

Set both SW1-5 and SW4-3 on ON for nominal 370 CFM/ton (+7% airflow).

This applies to Cooling and Low-Cooling airflow, but does not affect continuous fan airflow.

The above adjustments in airflow are subject to motor horsepower range/capacity.

2. Maximum cooling airflow is achieved when switches SW2-1, SW2-2, SW2-3 and SW1-5 are set to ON, and SW4-3 is set to OFF.

3. All heating CFM's are when comfort/efficiency adjustment switch (SW1-4) is set to OFF

4. Ductwork must be sized for high-heating CFM within the operational range of ESP. Operation within the blank areas of the chart is not recommended because high-heat operation will be

above 1.0 ESP.

5. All airflows on 21" casing size furnaces are 5% less on side return only installations.

(SW1-5 and SW4-3 set to OFF, except as indicated. See Footnotes

and

)

Unit Size: 60110C21 Clg/CF Switch Settings External Static Pressure (ESP)

Clg Switches SW2-3 SW2-2 SW2-1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Clg Default: OFF OFF OFF 1750 1750 1750 1750 1750 1750 1750 1750 1740 1725

CF Switches SW3-3 SW3-2 SW3-1

Low-Clg Default:

OFF OFF OFF 875 875 875 875 875 See Note

Cooling Airflow

(SW2)

Low-Cooling Airflow

(SW3)

OFF OFF ON 700 700 700 700 700 See Note

OFF ON OFF 875 875 875 875 875 See Note

OFF ON ON 1050 1050 1050 1050 1050 See Note

ON OFF OFF 1225 1225 1225 1225 1225 1225 1225 1225 1225 1225

ON OFF ON 1400 1400 1400 1400 1400 1400 1400 1400 1400 1400

ON ON OFF 1750 1750 1750 1750 1750 1750 1750 1750 1740 1725

ON ON ON 2100 2100 2100 2100 2090 2075 2055 2040 2005 1970

Maximum Clg Airflow

2200 2190 2190 2180 2155 2145 2125 2100 2080 2020

CF Switches SW3-3 SW3-2 SW3-1

Cont. Fan Default:

OFF OFF OFF 875 875 875 875 875 See Note

Continuous Fan

Airflow (SW3)

OFF OFF ON 700 700 700 700 700 See Note

OFF ON OFF 875 875 875 875 875 See Note

OFF ON ON 1050 1050 1050 1050 1050 See Note

ON OFF OFF 1225 1225 1225 1225 1225 1225 1225 1225 1225 1225

ON OFF ON 1400 1400 1400 1400 1400 1400 1400 1400 1400 1400

ON ON OFF 1400 1400 1400 1400 1400 1400 1400 1400 1400 1400

ON ON ON 1400 1400 1400 1400 1400 1400 1400 1400 1400 1400

Heating (SW1)

High Heat Airflow

1460 1465 1475 1475 1475 1475 1475 1475 1465 1465

Low Heat Airflow

1275 1295 1315 1320 1320 1320 1320 1320 1320 1315

Unit Size: 66135C24 Clg/CF Switch Settings External Static Pressure (ESP)

Clg Switches SW2-3 SW2-2 SW2-1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Clg Default: OFF OFF OFF 1750 1765 1765 1775 1780 1785 1785 1775 1770 1765

CF Switches SW3-3 SW3-2 SW3-1

Low-Clg Default: OFF OFF OFF 860 880 895 900 905 900 890 865 845 825

Cooling Airflow

(SW2)

Low-Cooling Airflow

(SW3)

OFF OFF ON 690 710 715 710 690 See Note

OFF ON OFF 860 880 895 900 905 900 890 865 845 825

OFF ON ON 1015 1050 1070 1080 1085 1095 1095 1090 1085 1075

ON OFF OFF 1185 1220 1245 1260 1270 1275 1280 1280 1285 1280

ON OFF ON 1400 1415 1420 1425 1425 1420 1415 1410 1400 1390

ON ON OFF 1750 1765 1765 1775 1780 1785 1785 1775 1770 1765

ON ON ON 2080 2095 2100 2110 2105 2115 2125 2115 2120 2090

Maximum Clg Airflow

2240 2255 2265 2270 2265 2255 2220 2175 2135 2085

CF Switches SW3-3 SW3-2 SW3-1

Cont. Fan Default: OFF OFF OFF 860 880 895 900 905 900 890 865 845 825

Continuous Fan

Airflow (SW3)

OFF OFF ON 690 710 715 710 690 See Note

OFF ON OFF 860 880 895 900 905 900 890 865 845 825

OFF ON ON 1015 1050 1070 1080 1085 1095 1095 1090 1085 1075

ON OFF OFF 1185 1220 1245 1260 1270 1275 1280 1280 1285 1280

ON OFF ON 1400 1415 1420 1425 1425 1420 1415 1410 1400 1390

ON ON OFF 1400 1415 1420 1425 1425 1420 1415 1410 1400 1390

ON ON ON 1400 1415 1420 1425 1425 1420 1415 1410 1400 1390

Heating (SW1)

High Heat Airflow

1825 1835 1850 1855 1860 1860 1855 1850 1845 1840

Low Heat Airflow

1645 1660 1670 1675 1675 1675 1675 1670 1665 1660

Table 13 – Air Delivery - CFM (With Filter) (Continued)

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

Table 14 – Furnace Setup Switch Description

A190151

A190150

Fig. 52 – Service Label

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

Table 15 – Orifice Size and Manifold Pressure (In. W.C.) for Gas Input Rate (Tabulated Data Based on 22,000 Btuh High-Heat/14,500 Btuh for

Low-Heat per Burner, Derated 4 Percent for Each 1000 Ft. (305 M) Above Sea Level)

ALTITUDE RANGE FT.

(M)

AVG. GAS HEAT

VALUE (BTUH/CU

FT.)

SPECIFIC GRAVITY OF NATURAL GAS

0.58 0.60 0.62 0.64

Orifice No.

Manifold

Pressure

High/Low

Orifice No.

Manifold

Pressure

High/Low

Orifice No.

Manifold

Pressure

High/Low

Orifice No.

Manifold

Pressure

High/Low

USA

0 to

2000

(0 to 610)

900 42 3.5/1.5 42 3.6/1.6 42 3.7/1.6 41 3.5/1.5

925 42 3.3/1.4 42 3.4/1.5 42 3.5/1.5 42 3.7/1.6

950 43 3.8/1.7 42 3.3/1.4 42 3.4/1.5 42 3.5/1.5

975 43 3.6/1.6 43 3.8/1.6 42 3.2/1.4 42 3.3/1.4

1000 43 3.5/1.5 43 3.6/1.6 43 3.7/1.6 43 3.8/1.7

1025 43 3.3/1.4 43 3.4/1.5 43 3.5/1.5 43 3.6/1.6

1050 44 3.6/1.6 43 3.2/1.4 43 3.4/1.5 43 3.5/1.5

1075 44 3.4/1.5 44 3.5/1.5 43 3.2/1.4 43 3.3/1.4

1100 44 3.3/1.4 44 3.4/1.5 44 3.5/1.5 43 3.2/1.4

USA

2001 to

3000

(610 to

914)

800 42 3.4/1.5 42 3.5/1.5 42 3.6/1.6 42 3.7/1.6

825 42 3.2/1.4 42 3.3/1.4 42 3.4/1.5 42 3.5/1.5

850 43 3.7/1.6 43 3.8/1.6 42 3.2/1.4 42 3.3/1.4

875 43 3.5/1.5 43 3.6/1.6 43 3.7/1.6 43 3.8/1.7

900 43 3.3/1.4 43 3.4/1.5 43 3.5/1.5 43 3.6/1.6

925 44 3.5/1.5 43 3.2/1.4 43 3.3/1.4 43 3.4/1.5

950 44 3.4/1.5 44 3.5/1.5 44 3.6/1.6 43 3.2/1.4

975 44 3.2/1.4 44 3.3/1.4 44 3.4/1.5 44 3.5/1.5

1000 45 3.7/1.6 45 3.8/1.7 44 3.2/1.4 44 3.4/1.5

USA

3001 to

4000

(914 to

1219)

775 42 3.2/1.4 42 3.3/1.4 42 3.4/1.5 42 3.5/1.5

800 43 3.6/1.6 43 3.8/1.6 42 3.2/1.4 42 3.3/1.4

825 43 3.4/1.5 43 3.5/1.5 43 3.7/1.6 43 3.8/1.6

850 43 3.2/1.4 43 3.3/1.4 43 3.4/1.5 43 3.6/1.5

875 44 3.5/1.5 44 3.6/1.6 43 3.3/1.4 43 3.4/1.5

900 44 3.3/1.4 44 3.4/1.5 44 3.5/1.5 43 3.2/1.4

925 45 3.8/1.6 44 3.2/1.4 44 3.3/1.5 44 3.4/1.5

950 46 3.8/1.6 45 3.7/1.6 45 3.8/1.7 44 3.3/1.4

USA

4001 to

5000

(1219 to

1524)

750 43 3.6/1.6 43 3.8/1.6 42 3.2/1.4 42 3.3/1.4

775 43 3.4/1.5 43 3.5/1.5 43 3.6/1.6 43 3.8/1.6

800 43 3.2/1.4 43 3.3/1.4 43 3.4/1.5 43 3.5/1.5

825 44 3.4/1.5 44 3.6/1.5 43 3.2/1.4 43 3.3/1.4

850 44 3.2/1.4 44 3.4/1.5 44 3.5/1.5 44 3.6/1.6

875 45 3.7/1.6 45 3.8/1.7 44 3.3/1.4 44 3.4/1.5

900 46 3.7/1.6 46 3.8/1.7 45 3.7/1.6 44 3.2/1.4

925 46 3.5/1.5 46 3.6/1.6 46 3.7/1.6 46 3.8/1.7

USA

5001 to

6000

(1524 to

1829)

725 43 3.4/1.5 43 3.5/1.5 43 3.6/1.6 43 3.7/1.6

750 43 3.2/1.4 43 3.3/1.4 43 3.4/1.5 43 3.5/1.5

775 44 3.4/1.5 44 3.5/1.5 43 3.2/1.4 43 3.3/1.4

800 44 3.2/1.4 44 3.3/1.4 44 3.4/1.5 44 3.5/1.5

825 46 3.8/1.7

45 3.8/1.6 44 3.2/1.4 44 3.3/1.4

850 46 3.6/1.6 46 3.7/1.6 46 3.8/1.7 45 3.8/1.6

875 47 3.8/1.7 46 3.5/1.5 46 3.6/1.6 46 3.7/1.6

900 47 3.6/1.6 47 3.8/1.6 46 3.4/1.5 46 3.5/1.5

USA

6001 to

7000

(1829 to

2134)

675 43 3.4/1.5 43 3.5/1.5 43 3.6/1.6 43 3.7/1.6

700 44 3.6/1.6 43 3.3/1.4 43 3.4/1.5 43 3.5/1.5

725 44 3.4/1.5 44 3.5/1.5 44 3.6/1.6 43 3.2/1.4

750 45 3.8/1.7 44 3.3/1.4 44 3.4/1.5 44 3.5/1.5

775 46 3.7/1.6 45 3.7/1.6 45 3.8/1.7 44 3.2/1.4

800 46 3.5/1.5 46 3.6/1.6 46 3.8/1.6 45 3.7/1.6

825 47 3.7/1.6 46 3.4/1.5 46 3.5/1.5 46 3.6/1.6

850 47 3.5/1.5 47 3.6/1.6 47 3.8/1.6 46 3.4/1.5

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

* Orifice numbers 43 are factory installed

USA

7001 to

8000

(2134 to

2438)

650 44 3.6/1.6 43 3.2/1.4 43 3.4/1.5 43 3.5/1.5

675 44 3.3/1.5 44 3.5/1.5 44 3.6/1.6 43 3.2/1.4

700 45 3.8/1.6 44 3.2/1.4 44 3.3/1.4 44 3.4/1.5

725 46 3.7/1.6 46 3.8/1.7 45 3.7/1.6 44 3.2/1.4

750 46 3.4/1.5 46 3.6/1.5 46 3.7/1.6 46 3.8/1.6

775 47 3.6/1.6 47 3.8/1.6 46 3.4/1.5 46 3.6/1.5

800 47 3.4/1.5 47 3.5/1.5 47 3.7/1.6 47 3.8/1.6

825 48 3.7/1.6 48 3.8/1.6 47 3.4/1.5 47 3.6/1.5

USA

8001 to

9000

(2438 to

2743)

625 44 3.3/1.5 44 3.5/1.5 44 3.6/1.6 43 3.2/1.4

650 45 3.7/1.6 44 3.2/1.4 44 3.3/1.4 44 3.4/1.5

675 46 3.6/1.6 46 3.8/1.6 45 3.7/1.6 45 3.8/1.7

700 47 3.8/1.7 46 3.5/1.5 46 3.6/1.6 46 3.7/1.6

725 47 3.6/1.6 47 3.7/1.6 47 3.8/1.7 46 3.5/1.5

750 48 3.8/1.7 47 3.5/1.5 47 3.6/1.6 47 3.7/1.6

775 48 3.6/1.5 48 3.7/1.6 48 3.8/1.7 47 3.5/1.5

USA

9001 to

10,000

2743 to

3048)

600 45 3.7/1.6 45 3.8/1.7 44 3.3/1.4 44 3.4/1.5

625 46 3.6/1.6 46 3.7/1.6 46 3.8/1.7 45 3.8/1.6

650 47 3.8/1.6 46 3.4/1.5 46 3.6/1.5 46 3.7/1.6

675 47 3.5/1.5 47 3.6/1.6 47 3.7/1.6 46 3.4/1.5

700 48 3.7/1.6 48 3.8/1.7 47 3.5/1.5 47 3.6/1.6

725 48 3.5/1.5 48 3.6/1.6 48 3.7/1.6 48 3.8/1.7

Table 15 – Orifice Size and Manifold Pressure (In. W.C.) for Gas Input Rate (Tabulated Data Based on 22,000 Btuh High-Heat/14,500 Btuh for

Low-Heat per Burner, Derated 4 Percent for Each 1000 Ft. (305 M) Above Sea Level) (Continued)

ALTITUDE RANGE FT.

(M)

AVG. GAS HEAT

VALUE (BTUH/CU

FT.)

SPECIFIC GRAVITY OF NATURAL GAS

0.58 0.60 0.62 0.64

Orifice No.

Manifold

Pressure

High/Low

Orifice No.

Manifold

Pressure

High/Low

Orifice No.

Manifold

Pressure

High/Low

Orifice No.

Manifold

Pressure

High/Low

Table 16 – Orifice Size and Manifold Pressure (In. W.C.) for Gas Input Rate (Tabulated Data Based on 21,000 Btuh High-Heat/14,500 Btuh

for Low-Heat Per Burner, Derated 4 Percent for Each 1000 Ft. (305 M) Above Sea level)

ALTITUDE RANGE FT.

(M)

AVG. GAS HEAT

VALUE (BTUH/CU

FT.)

SPECIFIC GRAVITY OF NATURAL GAS

0.58 0.60 0.62 0.64

Orifice No.

Manifold

Pressure

High/Low

Orifice No.

Manifold

Pressure

High/Low

Orifice No.

Manifold

Pressure

High/Low

Orifice No.

Manifold

Pressure

High/Low

USA

0 to

2000

(0 to 610)

900 42 3.2/1.5 42 3.3/1.6 42 3.4/1.6 42 3.5/1.7

925 43 3.7/1.8 43 3.8/1.8 42 3.2/1.5 42 3.3/1.6

950 43 3.5/1.7 43 3.6/1.7 43 3.7/1.8 43 3.8/1.8

975 43 3.3/1.6 43 3.4/1.6 43 3.5/1.7 43 3.7/1.7

1000 44 3.6/1.7 43 3.3/1.6 43 3.4/1.6 43 3.5/1.7

1025 44 3.4/1.6 44 3.6/1.7 43 3.2/1.5 43 3.3/1.6

1050 44 3.3/1.6 44 3.4/1.6 44 3.5/1.7 43 3.2/1.5

1075 45 3.8/1.8 44 3.2/1.5 44 3.3/1.6 44 3.4/1.6

1100 46 3.8/1.8 45 3.7/1.8 44 3.2/1.5 44 3.3/1.6

USA

2001 to

3000

(610 to

914)

800 43 3.8/1.8 42 3.2/1.5 42 3.3/1.6 42 3.4/1.6

825 43 3.5/1.7 43 3.7/1.7 43 3.8/1.8 42 3.2/1.5

850 43 3.3/1.6 43 3.5/1.6 43 3.6/1.7 43 3.7/1.8

875 43 3.2/1.5 43 3.3/1.6 43 3.4/1.6 43 3.5/1.7

900 44 3.4/1.6 44 3.5/1.7 43 3.2/1.5 43 3.3/1.6

925 44 3.2/1.5 44 3.3/1.6 44 3.5/1.6 44 3.6/1.7

950 45 3.7/1.8 45 3.8/1.8 44 3.3/1.6 44 3.4/1.6

975 46 3.7/1.8 46 3.8/1.8 45 3.8/1.8 44 3.2/1.5

1000 46 3.5/1.7 46 3.6/1.7 46 3.8/1.8 45 3.7/1.8

USA

3001 to

4000

(914 to

1219)

775 43 3.5/1.7 43 3.7/1.7 43 3.8/1.8 42 3.2/1.5

800 43 3.3/1.6 43 3.4/1.6 43 3.5/1.7 43 3.7/1.7

825 44 3.6/1.7 43 3.2/1.5 43 3.3/1.6 43 3.4/1.6

850 44 3.4/1.6 44 3.5/1.7 44 3.6/1.7 43 3.2/1.5

875 45 3.8/1.8 44 3.3/1.6 44 3.4/1.6 44 3.5/1.7

900 46 3.8/1.8 45 3.8/1.8 44 3.2/1.5 44 3.3/1.6

925 46 3.6/1.7 46 3.7/1.8 45 3.7/1.8 45 3.8/1.8

950 46 3.4/1.6 46 3.5/1.7 46 3.7/1.7 46 3.8/1.8

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

* Orifice numbers 43 are factory installed

SERVICE AND MAINTENANCE PROCEDURES

Untrained personnel can perform basic maintenance functions such as

cleaning and replacing air filters. All other operations must be performed

by trained service personnel. A qualified service person should inspect

the furnace once a year.

USA

4001 to

5000

(1219 to

1524)

750 43 3.3/1.6 43 3.4/1.6 43 3.5/1.7 43 3.6/1.7

775 44 3.6/1.7 43 3.2/1.5 43 3.3/1.6 43 3.4/1.6

800 44 3.3/1.6 44 3.4/1.6 44 3.6/1.7 43 3.2/1.5

825 45 3.8/1.8 44 3.2/1.5 44 3.4/1.6 44 3.5/1.6

850 46 3.8/1.8 45 3.7/1.8 45 3.8/1.8 44 3.3/1.6

875 46 3.5/1.7 46 3.7/1.7 46 3.8/1.8 45 3.7/1.8

900 47 3.8/1.8 46 3.5/1.7 46 3.6/1.7 46 3.7/1.8

925 47 3.6/1.7 47 3.7/1.8 47 3.8/1.8 46 3.5/1.7

USA

5001 to

6000

(1524 to

1829)

725 44 3.5/1.7 43 3.2/1.5 43 3.3/1.6 43 3.4/1.6

750 44 3.3/1.6 44 3.4/1.6 44 3.5/1.7 43 3.2/1.5

775 45 3.7/1.8 44 3.2/1.5 44 3.3/1.6 44 3.4/1.6

800 46 3.7/1.8 46 3.8/1.8 45 3.8/1.8 44 3.2/1.5

825 46 3.5/1.7 46 3.6/1.7 46 3.7/1.8 46 3.8/1.8

850 47 3.7/1.8 47 3.8/1.8 46 3.5/1.7 46 3.6/1.7

875 47 3.5/1.7 47 3.6/1.7 47 3.7/1.8 46 3.4/1.6

900 48 3.8/1.8 47 3.4/1.6 47 3.5/1.7 47 3.7/1.7

USA

6001 to

7000

(1829 to

2134)

675 44 3.5/1.7 43 3.2/1.5 43 3.3/1.6 43 3.4/1.6

700 44 3.3/1.6 44 3.4/1.6 44 3.5/1.7 43 3.2/1.5

725 45 3.7/1.8 45 3.8/1.8 44 3.3/1.6 44 3.4/1.6

750 46 3.6/1.7 46 3.8/1.8 45 3.7/1.8 45 3.8/1.8

775 46 3.4/1.6 46 3.5/1.7 46 3.6/1.7 46 3.8/1.8

800 47 3.6/1.7 47 3.8/1.8 46 3.4/1.6 46 3.5/1.7

825 47 3.4/1.6 47 3.5/1.7 47 3.6/1.7 47 3.8/1.8

850 48 3.7/1.7 48 3.8/1.8 47 3.4/1.6 47 3.5/1.7

USA

7001 to

8000

(2134 to

2438)

650 44 3.3/1.6 44 3.4/1.6 44 3.5/1.7 43 3.2/1.5

675 45 3.7/1.8 45 3.8/1.8 44 3.3/1.6 44 3.4/1.6

700 46 3.6/1.7 46 3.7/1.8 46 3.8/1.8 45 3.8/1.8

725 47 3.8/1.8 46 3.5/1.7 46 3.6/1.7 46 3.7/1.8

750 47 3.5/1.7 47 3.7/1.8 47 3.8/1.8 46 3.5/1.6

775 48 3.8/1.8 47 3.4/1.6 47 3.6/1.7 47 3.7/1.7

800 48 3.6/1.7 48 3.7/1.8 48 3.8/1.8 47 3.4/1.6

825 48 3.3/1.6 48 3.5/1.6 48 3.6/1.7 48 3.7/1.8

USA

8001 to

9000

(2438 to

2743)

625 45 3.7/1.8 45 3.8/1.8 44 3.3/1.6 44 3.4/1.6

650 46 3.6/1.7 46 3.7/1.8 46 3.8/1.8 45 3.8/1.8

675 47 3.8/1.8 46 3.4/1.6 46 3.5/1.7 46 3.7/1.7

700 47 3.5/1.7 47 3.6/1.7 47 3.7/1.8 46 3.4/1.6

725 48 3.7/1.8 48 3.8/1.8 47 3.5/1.7 47 3.6/1.7

750 48 3.5/1.7 48 3.6/1.7 48 3.7/1.8 48 3.8/1.8

775 49 3.8/1.8 48 3.4/1.6 48 3.5/1.7 48 3.6/1.7

USA

9001 to

10,000

(2743 to

3048)

600 46 3.6/1.7 46 3.7/1.8 46 3.8/1.8 45 3.7/1.8

625 47 3.7/1.8 47

3.8/1.8 46 3.5/1.7 46 3.6/1.7

650 47 3.4/1.6 47 3.6/1.7 47 3.7/1.8 47 3.8/1.8

675 48 3.6/1.7 48 3.8/1.8 47 3.4/1.6 47 3.5/1.7

700 48 3.4/1.6 48 3.5/1.7 48 3.6/1.7 48 3.7/1.8

725 49 3.7/1.8 49 3.8/1.8 48 3.4/1.6 48 3.5/1.7

Table 16 – Orifice Size and Manifold Pressure (In. W.C.) for Gas Input Rate (Tabulated Data Based on 21,000 Btuh High-Heat/14,500 Btuh

for Low-Heat Per Burner, Derated 4 Percent for Each 1000 Ft. (305 M) Above Sea level) (Continued)

ALTITUDE RANGE FT.

(M)

AVG. GAS HEAT

VALUE (BTUH/CU

FT.)

SPECIFIC GRAVITY OF NATURAL GAS

0.58 0.60 0.62 0.64

Orifice No.

Manifold

Pressure

High/Low

Orifice No.

Manifold

Pressure

High/Low

Orifice No.

Manifold

Pressure

High/Low

Orifice No.

Manifold

Pressure

High/Low

WARNING

FIRE, INJURY OR DEATH HAZARD

Failure to follow this warning could result in personal injury, death

and/or property damage.

The ability to properly perform maintenance on this equipment requires

certain knowledge, mechanical skills, tools, and equipment. If you do

not possess these, do not attempt to perform any maintenance on this

equipment other than those procedures recommended in the User’s

Manual.

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

GENERAL

These instructions are written as if the furnace is installed in an upflow

application. An upflow furnace application is where the blower is

located below the combustion and controls section of the furnace, and

conditioned air is discharged upward. Since this furnace can be installed

in any of 4 positions, see in Fig. 6, you must revise your orientation to

component location accordingly.

Electrical Controls and Wiring

The electrical ground and polarity for 115-v wiring must be properly

maintained. See Fig. 24 for field wiring information, and see Fig. 56 in

the Wiring Diagram section for furnace wiring information.

NOTE: If the polarity is not correct, the STATUS LED on the control

will flash rapidly and prevent the furnace from heating. The control

system also requires an earth ground for proper operation of the control

and flame-sensing electrode.

The 24-v circuit contains an automotive-type, 3-amp. fuse located on the

control, see Fig. 35. Any shorts of the 24-v wiring during installation,

service, or maintenance will cause this fuse to blow. If fuse replacement

is required, use ONLY a 3-amp. fuse. The control LED will display

status code 24 when fuse needs to be replaced.

Proper instrumentation is required to service electrical controls. The

control in this furnace is equipped with a Status Code LED

(Light-Emitting Diode) to aid in installation, servicing, and

troubleshooting. Status codes can be viewed at the sight glass in blower

access door. The amber furnace control LED is either ON continuously,

rapid flashing, or a code composed of 2 digits. The first digit is the

number of short flashes, the second digit is the number of long flashes.

For an explanation of status codes, refer to service label located on

blower access door (also on Fig. 52), and the troubleshooting guide

which can be obtained from your distributor.

See the brief Troubleshooting Guide, see Fig. 57.

For 2-Stage Variable Speed ECM Controls the stored status codes will

NOT be erased from the control memory, when 115- or 24-v power is

interrupted. The control will store up to the last 7 Status Codes in order

of occurrence.

1. To retrieve status codes, proceed with the following:

NOTE: NO thermostat signal may be present at control, and all

blower-OFF delays must be completed.

a. Leave 115-v power to furnace turned on.

b. Remove outer access door.

c. Look into blower access door sight glass for current LED status.

d. Remove blower access door.

NOTE: The Status Codes cannot be retrieved by disconnecting the limit

switch or draft safeguard switch. To retrieve Status Codes, follow the

procedure below.

2. Turn Setup Switch, SW1-1 “ON.”

3. Manually close blower access door switch.

4. Control will flash up to 7 Status Codes.

5. The last Status Code, or 8th Code, will be code 11.

6. Turn SW1-1 “OFF.”

7. The Amber LED will be continuously lit – which indicates proper

operation.

8. Release blower access door switch, install blower access door and

replace outer door, or refer to the SERVICE label on the front of the

blower access door for more information.

Component Self-Test

Component Test can ONLY be initiated by performing the following:

1. Remove outer access door.

2. Remove blower access door.

3. Remove the wire from the “R” terminal of the control board.

4. Turn Setup Switch, SW-1-6 “ON.”

5. Manually close blower access door switch.

Blower access door switch opens 115-v power to control. No component

operation can occur unless switch is closed. Caution must be taken when

manually closing this switch for service purposes.

6. Component Test sequence will function as follows:

a. Inducer motor starts on high-speed and continues to run until

Step (d.) of component test sequence.

b. Hot surface igniter is energized for 15 sec, then de-energized.

c. Blower operates for 10 sec, then turns off.

d. Inducer motor goes to low-speed for 10 seconds, then turns off.

CAUTION

ENVIRONMENTAL HAZARD

Failure to follow this caution may result in environmental pollution.

Remove and recycle all components or materials (i.e. oil, refrigerant,

control board, etc.) before unit final disposal.

WARNING

ELECTRICAL SHOCK, FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal injury or death,

or property damage.

Before installing, modifying, or servicing system, main electrical

disconnect switch must be in the OFF position and install a lockout tag.

There may be more than one disconnect switch. Lock out and tag

switch with a suitable warning label. Verify proper operation after

servicing.

CAUTION

ELECTRICAL OPERATION HAZARD

Failure to follow this caution may result in improper furnace operation

or failure of furnace.

Label all wires prior to disconnection when servicing controls. Wiring

errors can cause improper and dangerous operation.

WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury or death.

There may be more than one electrical supply to the furnace. Check

accessories and cooling unit for additional electrical supplies that must

be shut off during furnace servicing. Lock out and tag switch with a

suitable warning label.

WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury, or death.

Blower access door switch opens 115-v power to furnace control. No

component operation can occur unless switch is closed. Exercise

caution to avoid electrical shock from exposed electrical components

when manually closing this switch for service purposes.

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

e. After component test is completed, one or more status codes 11,

25 or 41 will flash. See component test section of service label

for explanation of status codes.

NOTE: To repeat component test, turn setup switch SW1-6 OFF then

back ON.

f. Turn setup switch SW1-6 OFF.

7. RELEASE BLOWER ACCESS DOOR SWITCH, reattach wire to

“R” terminal on furnace control board, replace blower access door,

and replace outer access door.

CARE AND MAINTENANCE

For continuing high performance and to minimize possible furnace

failure, periodic maintenance must be performed on this furnace.

Consult your local dealer about proper frequency of maintenance and the

availability of a maintenance contract.

The minimum maintenance on this furnace is as follows:

1. Check and clean air filter each month or more frequently if

required. Replace if torn.

2. Check blower motor and wheel for cleanliness each heating and

cooling season. Clean as necessary.

3. Check electrical connections for tightness and controls for proper

operation each heating season. Service as necessary.

4. Inspect burner compartment before each heating season for rust,

corrosion, soot or excessive dust. If necessary, have furnace and

burner serviced by a qualified service agency.

5. Inspect the vent pipe/vent system before each heating season for

rust, corrosion, water leakage, sagging pipes or broken fittings.

Have vent pipes/vent system serviced by a qualified service agency.

6. Inspect any accessories attached to the furnace such as a humidifier

or electronic air cleaner. Perform any service or maintenance to the

accessories as recommended in the accessory instructions.

Cleaning and/or Replacing Air Filter

The air filter arrangement will vary depending on the application.

NOTE: If the filter has an airflow direction arrow, the arrow must point

towards the blower.

Media Cabinet Filter Procedures:

Perform the following procedure to clean or replace a media cabinet

filter:

1. Turn off electrical supply to furnace before removing filter access

door.

2. Remove filter cabinet door.

3. Slide filter out of cabinet.

4. If equipped with permanent, washable 3/4-in. (19 mm) filter, clean

filter by spraying cold tap water through filter in opposite direction

of airflow. Rinse filter and let dry. Oiling or coating of the filter is

not recommended. See Table 17 for size information.

5. If equipped with factory-specified disposable media filter, replace

only with media filter having the same part number and size. For

expandable replacement media, refer to the instructions included

with the replacement media.

6. Slide filter into cabinet.

7. Replace filter cabinet door.

8. Turn on electrical supply to furnace.

WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal injury, death

and/or property damage.

Never store anything on, near, or in contact with the furnace, such as:

1. Spray or aerosol cans, rags, brooms, dust mops, vacuum cleaners,

or other cleaning tools.

2. Soap powders, bleaches, waxes or other cleaning compounds,

plastic or plastic containers, gasoline, kerosene, cigarette lighter

fluid, dry cleaning fluids, or other volatile fluids.

3. Paint thinners and other painting compounds, paper bags, or other

paper products. Exposure to these materials could lead to

corrosion of the heat exchangers.

WARNING

CARBON MONOXIDE POISONING AND FIRE

HAZARD

Failure to follow this warning could result in personal injury, death

and/or property damage.

Never operate furnace without a filter or with filter access door

removed.

WARNING

ELECTRICAL SHOCK AND FIRE HAZARD

Failure to follow this warning could result in personal injury, death,

and/or property damage.

Turn off the gas and electrical supplies to the furnace and install lockout

tag before performing any maintenance or service. Follow the operating

instructions on the label attached to the furnace.

CAUTION

CUT HAZARD

Failure to follow this caution may result in personal injury.

Sheet metal parts may have sharp edges or burrs. Use care and wear

appropriate protective clothing, safety glasses and gloves when

handling parts, and servicing furnaces.

CAUTION

CUT HAZARD

Failure to follow this caution may result in personal injury.

Sheet metal parts may have sharp edges or burrs. Use care and wear

appropriate protective clothing, safety glasses and gloves when

handling parts, and servicing furnaces.

Table 17 – Filter Size Information - In. (mm)

FURNACE

CASING WIDTH

FILTER SIZE

FILTER TYPE

SIDE

RETURN

BOTTOM

RETURN

14-1/2 (368)

16 x 25 x 3/4

(406 x 635 x 19)

14 x 25 x 3/4

(356 x 635 x 19)

Washable

*. Recommended

17-1/2 (445)

16 x 25 x 3/4

(406 x 635 x 19)

16 x 25 x 3/4

(406 x 635 x 19)

Washable

21 (533)

16 x 25 x 3/4

(406 x 635 x 19)

20 x 25 x 3/4

(508 x 635 x 19)

Washable

24 (610)

16 x 25 x 3/4

(406 x 635 x 19)

24 x 25 x 3/4

(610 x 635 x 19)

Washable

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

Blower Motor and Wheel

To ensure long life and high efficiency, clean accumulated dirt and

grease from blower wheel and motor annually.

The steps given here for the blower motor and wheel should be

performed by a qualified service agency.

The inducer and blower motors are pre-lubricated and require no

additional lubrication. These motors can be identified by the absence of

oil ports on each end of the motor.

NOTE: The blower wheel should not be dropped or bent as balance will

be affected.

Clean blower motor and wheel as follows:

1. Turn off electrical supply to furnace.

2. Remove outer door.

3. For downflow or horizontal furnaces having vent pipes within the

furnace that pass in front of the blower access door:

a. Disconnect vent connector from furnace vent elbow.

b. Disconnect and remove short piece of vent pipe from within

furnace.

4. Remove 2 screws from blower access door and remove blower

access door.

5. All factory wires can be left connected, but field thermostat

connections may need to be disconnected depending on their length

and routing.

6. Remove 2 screws holding blower assembly to blower deck and

slide blower assembly out of furnace.

7. Clean blower wheel and motor using a vacuum with soft brush

attachment. Blower wheel blades may be cleaned with a small paint

or flux brush. Do not remove or disturb balance weights (clips) on

blower wheel blades.

8. Vacuum any loose dust from blower housing, wheel and motor.

9. If a greasy residue is present on blower wheel, remove wheel from

the blower housing and wash it with an appropriate degreaser.

NOTE: Before disassembly, mark blower mounting arms, motor, and

blower housing so motor and each arm is positioned at the same location

during reassembly.

To remove wheel:

a. Disconnect ground wire attached to blower housing.

b. Remove screws securing cutoff plate and remove cutoff plate

from housing.

c. Loosen set screw holding blower wheel on motor shaft (160+/-20

in.-lb. when assembling).

d. Remove bolts holding motor to blower housing and slide motor

out of wheel (40+/-10 in.-lb. when reassembling).

e. Remove blower wheel from housing.

f. Clean wheel and housing.

10. Reassemble motor and blower by reversing steps 9a, through 9e. Be

sure to reattach ground wire to the blower housing.

11. Verify that blower wheel is centered in blower housing and set

screw contacts the flat portion of the motor shaft. Loosen set screw

on blower wheel and reposition if necessary.

12. Spin the blower wheel by hand to verify that the wheel does not rub

on the housing.

13. Reinstall blower assembly in furnace.

14. Reinstall 2 screws securing blower assembly to blower deck.

15. Reconnect blower leads to furnace control. Refer to furnace wiring

diagram, and connect thermostat leads if previously disconnected.

16. To check blower for proper rotation:

a. Turn on electrical supply.

b. Manually close blower access door switch.

NOTE: If R-W/W1 thermostat terminals are jumpered at the time

blower access door switch is closed, blower will run for 90 sec before

beginning a heating cycle.

c. Perform component self-test as shown at the bottom of the

SERVICE label, located on the front of blower access door.

d. Verify blower is rotating in the correct direction

17. If furnace is operating properly, RELEASE BLOWER ACCESS

DOOR SWITCH. Remove any jumpers or reconnect any

disconnected thermostat leads. Replace blower access door.

18. Downflow or horizontal furnaces with vent pipe through furnace

only:

a. Install and connect short piece of vent pipe inside furnace to

existing vent.

b. Connect vent connector to vent elbow.

19. Reinstall outer door.

20. Turn on gas supply and cycle furnace through one complete heating

and cooling cycle. Verify the furnace temperature rise as shown in

Adjustments Section. Adjust temperature rise as shown in

Adjustments Section. If outdoor temperature is below 70°F, turn off

circuit breaker to outdoor unit before running furnace in the cooling

cycle. Turn outdoor circuit breaker on after completing cooling

cycle.

Cleaning Heat Exchanger

The steps given here for cleaning heat exchangers should be performed

by a qualified service agency.

NOTE: If the heat exchangers get a heavy accumulation of soot and

carbon, they should be replaced rather than trying to clean them

thoroughly. A build-up of soot and carbon indicates that a problem exists

which needs to be corrected, such as improper adjustment of manifold

pressure, insufficient or poor quality combustion air, incorrect size or

damaged manifold orifice(s), improper gas, or a restricted heat

exchanger. Action must be taken to correct the problem.

If it becomes necessary to clean the heat exchangers because of dust or

corrosion, proceed as follows:

1. Turn OFF gas and electrical power to furnace.

2. Remove outer access door.

3. Disconnect vent connector from furnace vent elbow.

4. For downflow or horizontal furnace having an internal vent pipe,

remove internal vent pipe within the casing.

5. Disconnect wires to the following components. Mark wires to aid in

reconnection (be careful when disconnecting wires from switches

because damage may occur):

a. Draft safeguard switch.

b. Inducer motor.

WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury or death.

Blower access door switch opens 115-v power to control. No

component operation can occur unless switch is closed. Caution must

be taken when manually closing this switch for service purposes.

WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury, or death.

Blower access door switch opens 115-v power to furnace control. No

component operation can occur unless switch is closed. Exercise

caution to avoid electrical shock from exposed electrical components

when manually closing this switch for service purposes.

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

c. Pressure switches.

d. Limit overtemperature switch.

e. Gas valve.

f. Hot surface igniter.

g. Flame-sensing electrode.

h. Flame rollout switches.

6. Remove screws that fasten the collector box assembly to the cell

panel. Be careful not to damage the collector box. Inducer assembly

and elbow need not be removed from collector box.

7. Disconnect gas line from gas manifold.

8. Remove the four screws that attach the burner assembly to the cell

panel. The gas valve and individual burners need not be removed

from support assembly. Remove NOx baffles, if installed.

NOTE: Be very careful when removing burner assembly to avoid

breaking igniter. See Fig. 53 - Fig. 54 for correct igniter location.

A05026

Fig. 53 – Igniter Position - Top View

A05025

Fig. 54 – Igniter Position - Side View

NOTE: The materials needed in Step 9 can usually be purchased at local

hardware stores.

9. Using a field-provided 25-caliber rifle cleaning brush; a 36-in. (914

mm) long, 1/4-in. (6 mm) diameter steel spring cable; and a

variable speed drill, do the following:

a. Remove metal screw fitting from wire brush to allow insertion

into cable.

b. Insert the twisted wire end of brush into end of spring cable, and

crimp tight with crimping tool or crimp by striking with

ball-peen hammer. TIGHTNESS IS VERY IMPORTANT. After

crimping:

(1.) Attach variable-speed, reversible drill to the end of spring

cable (end opposite brush).

(2.) Insert brush end of cable into the outlet opening of cell and

slowly rotate with drill, see Fig. 55. DO NOT force cable.

Gradually insert cable into upper pass of cell.

A91252

Fig. 55 – Cleaning Heat Exchanger Cell

(3.) Work cable in and out of cell 3 or 4 times to obtain

sufficient cleaning. DO NOT pull cable with great force.

Reverse drill and gradually work cable out.

(4.) Insert brush end of cable in burner inlet opening of cell, and

proceed to clean 2 lower passes of cell in same manner as

upper pass.

(5.) Repeat foregoing procedures until each cell in furnace has

been cleaned.

(6.) Using vacuum cleaner, remove residue from each cell.

(7.) Using vacuum cleaner with soft brush attachment, clean

burner assembly.

(8.) Clean flame sensor with fine steel wool.

(9.) Install NOx baffles (if removed).

(10.)Reinstall burner assembly. Center burners in cell openings.

10. Remove old sealant from cell panel and collector box flange.

11. Spray releasing agent on the heat exchanger cell panel where

collector box assembly contacts cell panel.

NOTE: A releasing agent such as cooking spray or equivalent (must not

contain corn or canola oil, aromatic or halogenated hydrocarbons or

inadequate seal may occur) and RTV sealant (G.E. 162, 6702, or

Dow-Corning 738) are needed before starting installation. DO NOT

substitute any other type of RTV sealant. G.E. 162 (P771-9003) is

available through RCD in 3-oz tubes.

12. Apply new sealant to flange of collector box and attach to cell panel

using existing screws, making sure all screws are secure.

13. Reconnect wires to the following components (Use connection

diagram on wiring label, if wires were not marked for reconnection

locations.):

a. Draft safeguard switch.

b. Inducer motor.

c. Pressure switches.

d. Limit overtemperature switch.

e. Gas valve.

f. Hot surface igniter.

g. Flame-sensing electrode.

h. Flame rollout switches.

14. Reinstall internal vent pipe, if applicable.

15. Reinstall vent connector on furnace vent elbow. Securely fasten

vent connector to vent elbow with 2 field-supplied,

corrosion-resistant, sheet metal screws located 180° apart.

16. Replace blower access door only if it was removed.

17. Set thermostat above room temperature and check furnace for

proper operation.

18. Verify blower airflow and speed changes between heating and

cooling.

1-7/8

(47.6 mm)

9/32”

7.1mm

5/16”

7.9mm

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

19. Check for gas leaks.

SEQUENCE OF OPERATION

NOTE: Furnace control must be grounded for proper operation or else

control will lock out. Control is grounded through green/yellow wire

routed to gas valve and burner box screw. Using the schematic diagram

in Fig. 56, follow the sequence of operation through the different modes.

Read and follow the wiring diagram very carefully.

NOTE: If a power interruption occurs during a call for heat (W/W1 or

W/W1-and-W2), the control will start a 90-second blower-only ON

period two seconds after power is restored, if the thermostat is still

calling for gas heating. The amber LED light will flash code 12 during

the 90-second period, after which the LED will be ON continuous, as

long as no faults are detected. After the 90-second period, the furnace

will respond to the thermostat normally.

The blower door must be installed for power to be conducted through the

blower door interlock switch ILK to the furnace control CPU,

transformer TRAN, inducer motor IDM, blower motor BLWM,

hot-surface igniter HSI, and gas valve GV.

1. Perfect Heat

Technology - Two-Stage Heating (Adaptive

Mode) with Single-Stage Thermostat.

See Fig. 28 - Fig. 34 for thermostat connections.

NOTE: The low-heat only switch SW1-2 selects either the low-heat

only operation mode when ON, (see item 2. below) or the adaptive

heating mode when OFF in response to a call for heat, see Table 14.)

When the W2 thermostat terminal is energized it will always cause

high-heat operation when the R-to-W circuit is closed, regardless of the

setting of the low-heat only switch. This furnace can operate as a

two-stage furnace with a single-stage thermostat because the furnace

control CPU includes a programmed adaptive sequence of controlled

operation, which selects low-heat or high-heat operation. This selection

is based upon the stored history of the length of previous gas-heating

periods of the single-stage thermostat.

The furnace will start up in either low- or high-heat. If the furnace starts

up in low-heat, the control CPU determines the low-heat on-time (from 0

to 16 minutes) which is permitted before switching to high-heat.

If the power is interrupted, the stored history is erased and the control

CPU will select low-heat for up to 16 minutes and then switch to

high-heat, as long as the thermostat continues to call for heat.

Subsequent selection is based on stored history of the thermostat cycle

times.

The wall thermostat “calls for heat”, closing the R-to-W circuit. The

furnace control performs a self-check, verifies the low-heat and

high-heat pressure switch contacts LPS and HPS are open, and starts the

inducer motor IDM in high-speed.

a. Inducer Prepurge Period

(1.) If the furnace control CPU selects low-heat operation the

inducer motor IDM comes up to speed, the low-heat

pressure switch LPS closes, and the furnace control CPU

begins a 15-second prepurge period. If the low-heat pressure

switch LPS fails to remain closed, the inducer motor IDM

will remain running at high-speed. After the low-heat

pressure switch re-closes, the furnace control CPU will

begin a 15-second prepurge period, and continue to run the

inducer motor IDM at high-speed.

(2.) If the furnace control CPU selects high-heat operation, the

inducer motor IDM remains running at high-speed, and the

high-heat pressure switch relay HPSR is de-energized to

close the NC contact. When sufficient pressure is available

the high-heat pressure switch HPS closes, and the high-heat

gas valve solenoid GV-HI is energized. The furnace control

CPU begins a 15-second prepurge period after the low-heat

pressure switch LPS closes. If the high-heat pressure switch

HPS fails to close and the low-heat pressure switch LPS

closes, the furnace will operate at low-heat gas flow rate

until the high-heat pressure switch closes for a maximum of

2 minutes after ignition.

b. Igniter Warm-Up -At the end of the prepurge period, the

Hot-Surface Igniter HSI is energized for a 17-second igniter

warm-up period.

c. Trial-For-Ignition Sequence -When the igniter warm-up period

is completed the main gas valve relay contact GVR closes to

energize the gas valve solenoid GV-M. The gas valve solenoid

GV-M permits gas flow to the burners where it is ignited by the

HSI. Five seconds after the GVR closes, a 2-second flame

proving period begins. The HSI igniter will remain energized

until the flame is sensed or until the 2-second flame proving

period begins. If the furnace control CPU selects high-heat

operation, the high-heat gas valve solenoid GV-HI is also

energized.

d. Flame-Proving - When the burner flame is proved at the

flame-proving sensor electrode FSE, the inducer motor IDM

switches to low-speed unless the furnace is operating in

high-heat, and the furnace control CPU begins the blower-ON

delay period and continues to hold the gas valve GV-M open. If

the burner flame is not proved within two seconds, the control

CPU will close the gas valve GV-M, and the control CPU will

repeat the ignition sequence for up to three more

Trials-For-Ignition before going to Ignition-Lockout. Lockout

will be reset automatically after three hours, or by momentarily

interrupting 115 vac power to the furnace, or by interrupting 24

vac power at SEC1 or SEC2 to the furnace control CPU (not at

W/W1, G, R, etc.). If flame is proved when flame should not be

present, the furnace control CPU will lock out of Gas-Heating

mode and operate the inducer motor IDM on high speed until

flame is no longer proved.

e. Blower-On delay - If the burner flame is proven the blower-ON

delays for low-heat and high-heat are as follows:

Low-Heat - 45 seconds after the gas valve GV-M is opened the blower

motor BLWM is turned ON at low-heat airflow.

High-Heat - 25 seconds after the gas valve GV-M is opened the BLWM

is turned ON at high-heat airflow. Simultaneously, the humidifier

terminal HUM and electronic air cleaner terminal EAC-1 are energized

and remain energized throughout the heating cycle.

f. Switching from Low- to High-Heat - If the furnace control

CPU switches from low-heat to high-heat, the furnace control

CPU will switch the inducer motor IDM speed from low to high.

The high-heat pressure switch relay HPSR is de-energized to

close the NC contact. When sufficient pressure is available the

high-heat pressure switch HPS closes, and the high-heat gas

valve solenoid GV-HI is energized. The blower motor BLWM

will transition to high-heat airflow five seconds after the furnace

control CPU switches from low-heat to high-heat.

g. Switching from High- to Low-Heat -The furnace control CPU

will not switch from high-heat to low-heat while the thermostat

R-to-W circuit is closed when using a single-stage thermostat.

WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal injury, death,

and/or property damage.

Never purge a gas line into a combustion chamber. Never test for gas

leaks with an open flame. Use a commercially available soap solution

made specifically for the detection of leaks to check all connections. A

fire or explosion may result causing property damage, personal injury

or loss of life.

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

h. Blower-Off Delay -When the thermostat is satisfied, the R to W

circuit is opened, de-energizing the gas valve GV-M, stopping

gas flow to the burners, and de-energizing the humidifier

terminal HUM. The inducer motor IDM will remain energized

for a 5-second post-purge period. The blower motor BLWM and

air cleaner terminal EAC-1 will remain energized at low-heat

airflow or transition to low-heat airflow for 90, 120, 150, or 180

seconds (depending on selection at blower-OFF delay switches).

The furnace control CPU is factory-set for a 120-second

blower-OFF delay.

2. Two-Stage Thermostat and Two-Stage Heating

See Fig. 28 - Fig. 34 for thermostat connections.

NOTE: In this mode the low-heat only switch SW1-2 must be ON to

select the low-heat only operation mode in response to closing the

thermostat R-to-W1 circuit. Closing the thermostat R-to- W1-and-W2

circuits always causes high-heat operation, regardless of the setting of

the low-heat only switch.

The wall thermostat “calls for heat”, closing the R-to-W1 circuit for

low-heat or closing the R-to-W1-and-W2 circuits for high-heat. The

furnace control performs a self-check, verifies the low-heat and

high-heat pressure switch contacts LPS and HPS are open, and starts the

inducer motor IDM in high-speed.

The start up and shut down functions and delays described in item 1.

above apply to the 2-stage heating mode as well, except for switching

from low- to high-Heat and vice versa.

a. Switching from Low- to High-Heat - If the thermostat R-to-W1

circuit is closed and the R-to-W2 circuit closes, the furnace

control CPU will switch the inducer motor IDM speed from low

to high. The high-heat pressure switch relay HPSR is

de-energized to close the NC contact. When sufficient pressure is

available the high-heat pressure switch HPS closes, and the

high-heat gas valve solenoid GV-HI is energized. The blower

motor BLWM will transition to high-heat airflow five seconds

after the R-to-W2 circuit closes.

b. Switching from High- to Low-Heat -If the thermostat R-to- W2

circuit opens, and the R-to-W1 circuit remains closed, the

furnace control CPU will switch the inducer motor IDM speed

from high to low. The high-heat pressure switch relay HPSR is

energized to open the NC contact and de-energize the high-heat

gas valve solenoid GV-HI. When the inducer motor IDM reduces

pressure sufficiently, the high-heat pressure switch HPS will

open. The gas valve solenoid GV-M will remain energized as

long as the low-heat pressure switch LPS remains closed. The

blower motor BLWM will transition to low-heat airflow five

seconds after the R-to-W2 circuit opens.

3. Cooling mode

The thermostat “calls for cooling.”

a. Single-Speed Cooling-

See Fig. for thermostat connections

The thermostat closes the R-to-G-and-Y circuits. The R-to- Y

circuit starts the outdoor unit, and the R-to-G-and-Y/Y2 circuits

start the furnace blower motor BLWM on cooling airflow.

Cooling airflow is based on the A/C selection shown in Fig. 14.

The electronic air cleaner terminal EAC-1 is energized with 115

vac when the blower motor BLWM is operating.

When the thermostat is satisfied, the R-to-G-and-Y circuits are

opened. The outdoor unit will stop, and the furnace blower motor

BLWM will continue operating at cooling airflow for an

additional 90 seconds. Jumper Y/Y2 to DHUM to reduce the

cooling off-delay to 5 seconds, see Fig. 35.

b. Single-Stage Thermostat and Two-Speed Cooling (Adaptive

Mode).

See Fig. for thermostat connections.

This furnace can operate a two-speed cooling unit with a

single-stage thermostat because the furnace control CPU

includes a programmed adaptive sequence of controlled

operation, which selects low-cooling or high-cooling operation.

This selection is based upon the stored history of the length of

previous cooling period of the single-stage thermostat.

NOTE: The air conditioning relay disable jumper ACRDJ must be

connected to enable the adaptive cooling mode in response to a call for

cooling, see Fig. 35. When ACRDJ is in place the furnace control CPU

can turn on the air conditioning relay ACR to energize the Y/Y2 terminal

and switch the outdoor unit to high-cooling.

The furnace control CPU can start up the cooling unit in either low- or

high-cooling. If starting up in low-cooling, the furnace control CPU

determines the low-cooling on-time (from 0 to 20 minutes) which is

permitted before switching to high-cooling. If the power is interrupted,

the stored history is erased and the furnace control CPU will select

low-cooling for up to 20 minutes and then energize the air conditioning

relay ACR to energize the Y/Y2 terminal and switch the outdoor unit to

high-cooling, as long as the thermostat continues to call for cooling.

Subsequent selection is based on stored history of the thermostat cycle

times.

The wall thermostat “calls for cooling”, closing the R-to-G-and-Y

circuits. The R-to-Y1 circuit starts the outdoor unit on low-cooling

speed, and the R-to-G-and-Y1 circuits starts the furnace blower motor

BLWM at low-cooling airflow which is the true on-board CF selection,

see Fig. 14.

If the furnace control CPU switches from low-cooling to high-cooling,

the furnace control CPU will energize the air conditioning relay ACR.

When the air conditioning relay ACR is energized the R-to-Y1-and-Y2

circuits switch the outdoor unit to high-cooling speed, and the

R-to-G-and-Y1-and-Y/Y2 circuits transition the furnace blower motor

BLWM to high-cooling airflow. High-cooling airflow is based on the

A/C selection, see Fig. 14.

NOTE: When transitioning from low-cooling to high-cooling the

outdoor unit compressor will shut down for 1 minute while the furnace

blower motor BLWM transitions to run at high-cooling airflow.

The electronic air cleaner terminal EAC-1 is energized with 115 vac

whenever the blower motor BLWM is operating.

When the thermostat is satisfied, the R-to-G-and-Y circuit are opened.

The outdoor unit stops, and the furnace blower BLWM and electronic air

cleaner terminal EAC-1 will remain energized for an additional 90

seconds. Jumper Y1 to DHUM to reduce the cooling off-delay to 5

seconds, see Fig. 35.

c. Two-Stage Thermostat and Two-Speed Cooling

See Fig. 34 for thermostat connections

NOTE: The air conditioning relay disable jumper ACRDJ must be

disconnected to allow thermostat control of the outdoor unit staging, see

Fig. 35.

d. The thermostat closes the R-to-G-and-Y1 circuits for

low-cooling or closes the R-to-G-and-Y1-and-Y2 circuits for

high-cooling. The R-to-Y1 circuit starts the outdoor unit on

low-cooling speed, and the R-to-G-and-Y1 circuit starts the

furnace blower motor BLWM at low-cooling airflow which is the

true on-board CF (continuous fan) selection, see Fig. 14. The

R-to-Y1-and-Y2 circuits start the outdoor unit on high-cooling

speed, and the R-to-G-and-Y/Y2 circuits start the furnace blower

motor BLWM at high-cooling airflow. High-cooling airflow is

based on the A/C (air conditioning) selection, see Fig. 14.

The electronic air cleaner terminal EAC-1 is energized with 115

vac whenever the blower motor BLWM is operating.

When the thermostat is satisfied, the R-to-G-and-Y1 or R-to-

G-and-Y1-and-Y2 circuits are opened. The outdoor unit stops,

and the furnace blower BLWM and electronic air cleaner

terminal EAC-1 will remain energized for an additional 90

seconds. Jumper Y1 to DHUM to reduce the cooling off-delay to

5 seconds, see Fig. 35.

4. Dehumidify Mode

See Fig. 28 - Fig. 34 for thermostat connections.

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

The dehumidification output, DHUM on the Thermostat should be

connected to the furnace control thermostat terminal DHUM. When

there is a dehumidify demand, the DHUM input is activated, which

means 24 vac signal is removed from the DHUM input terminal. In

other words, the DHUM input logic is reversed. The DHUM input

is turned ON when no dehumidify demand exists. Once 24 vac is

detected by the furnace control on the DHUM input, the furnace

control operates in dehumidify mode. If the DHUM input is low for

more than 48 hours, the furnace control reverts back to

non-dehumidify mode.

The cooling operation described in item 3. above also applies to

operation with a thermostat. The exceptions are listed below:

a. Low cooling-When the R-to-G-and-Y1 circuit is closed and

there is a demand for dehumidification, the furnace blower motor

BLWM will drop the blower airflow to 86 percent of low-cooling

airflow which is the true on-board CF (continuous fan) selection,

see Fig. 14.

b. High cooling-When the R-to-G-and Y/Y2 circuit is closed and

there is a demand for dehumidification, the furnace blower motor

BLWM will drop the blower airflow to 86 percent of

high-cooling airflow. High-cooling airflow is based on the A/C

(air conditioning) selection, see Fig. 14.

c. Cooling off-delay-When the “call for cooling” is satisfied and

there is a demand for dehumidification, the cooling blower-off

delay is decreased from 90 seconds to 5 seconds.

5. Super-Dehumidify Mode

Super-Dehumidify mode can only be entered if the furnace control

is in the Dehumidify mode and there is a demand for

dehumidification. The cooling operation described in item 3. above

also applies to operation with a thermostat. The exceptions are

listed below:

a. When the R-to-Y1 circuit is closed, R-to-G circuit is open, and

there is a demand for dehumidification, the furnace blower motor

BLWM will drop the blower airflow to 65 percent of low-cooling

airflow for a maximum of 10 minutes each cooling cycle or until

the R-to-G circuit closes or the demand for dehumidification is

satisfied. Low-cooling airflow is the true on-board CF

(continuous fan) selection, see Fig. 14.

b. When the R-to-Y/Y2 circuit is closed, R-to-G circuit is open, and

there is a demand for dehumidification, the furnace blower motor

BLWM will drop the blower airflow to 65 percent of

high-cooling airflow for a maximum of 10 minutes each cooling

cycle or until the R-to-G circuit closes or the demand for

dehumidification is satisfied. High-cooling airflow is based on

the A/C (air conditioning) selection, see Fig. 14.

c. When the “call for cooling” is satisfied and there is a demand for

dehumidification, the cooling blower-off delay is decreased from

90 seconds to 5 seconds.

6. Continuous Blower Mode

When the R-to-G circuit is closed by the thermostat, the blower

motor BLWM will operate at continuous blower airflow.

Continuous blower airflow selection is initially based on the CF

(continuous fan) selection, see Fig. 14. (The factory default is

shown in Fig. 14. Terminal EAC-1 is energized as long as the

blower motor BLWM is energized.

During a call for heat, the furnace control CPU will transition the

blower motor BLWM to continuous blower airflow, low-heat

airflow, or the mid-range airflow, whichever is lowest. The blower

motor BLWM will remain ON until the main burners ignite then

shut OFF and remain OFF for the blower-ON delay (45 seconds in

low-heat, and 25 seconds in high-heat), allowing the furnace heat

exchangers to heat up more quickly, then restarts at the end of the

blower-ON delay period at low-heat or high-heat airflow,

respectively.

The blower motor BLWM will revert to continuous-blower airflow

after the heating cycle is completed. In high-heat, the furnace

control CPU will drop the blower motor BLWM to low-heat airflow

during the selected blower-OFF delay period before transitioning to

continuous-blower airflow.

When the thermostat “calls for low-cooling”, the blower motor

BLWM will switch to operate at low-cooling airflow. When the

thermostat is satisfied, the blower motor BLWM will operate an

additional 90 seconds at low-cooling airflow before transitioning

back to continuous-blower airflow.

When the thermostat “calls for high-cooling”, the blower motor

BLWM will operate at high cooling airflow. When the thermostat is

satisfied, the blower motor BLWM will operate an additional 90

seconds at high-cooling airflow before transitioning back to

continuous-blower airflow. When the R-to-G circuit is opened, the

blower motor BLWM will continue operating for an additional 5

seconds, if no other function requires blower motor BLWM

operation.

Continuous Blower Speed Selection from Thermostat

To select different continuous-blower airflow from the room thermostat,

momentarily turn off the FAN switch or push button on the room

thermostat for 1-3 seconds after the blower motor BLWM is operating.

The furnace control CPU will shift the continuous-blower airflow from

the factory setting to the next highest CF selection airflow, see Fig. 14.

Momentarily turning off the FAN switch again at the thermostat will

shift the continuous-blower airflow up one more increment. If you repeat

this procedure enough you will eventually shift the continuous-blower

airflow to the lowest CF selection, see Fig. 14. The selection can be

changed as many times as desired and is stored in the memory to be

automatically used following a power interruption.

NOTE: If the blower-off delay is set to the maximum, the adjustable

continuous-fan feature is locked (i.e., fan speed cannot be changed from

its current setting).

7. Heat pump

See Fig. 32 - Fig. 33for thermostat connections.

When installed with a heat pump, the furnace control automatically

changes the timing sequence to avoid long blower off times during

demand defrost cycles. Whenever W/W1 is energized along with

Y1 or Y/Y2, the furnace control CPU will transition to or bring on

the blower motor BLWM at cooling airflow, low-heat airflow, or

the mid-range airflow, whichever is lowest. The blower motor

BLWM will remain on until the main burners ignite then shut OFF

and remain OFF for 25 seconds before coming back on at heating

airflow. When the W/W1 input signal disappears, the furnace

control begins a normal inducer post-purge period while changing

the blower airflow. If Y/Y2 input is still energized the furnace

control CPU will transition the blower motor BLWM airflow to

cooling airflow. If Y/Y2 input signal disappears and the Y1 input is

still energized the furnace control CPU will transition the blower

motor BLWM to low-cooling airflow. If both the Y1 and Y/Y2

signals disappear at the same time, the blower motor BLWM will

remain on at low-heat airflow for the selected blower-OFF delay

period. At the end of the blower- OFF delay, the blower motor

BLWM will shut OFF unless G is still energized, in which case the

blower motor BLWM will operate at continuous blower airflow.

8. Component test

The furnace features a component test system to help diagnose a

system problem in the case of a component failure. To initiate the

component test procedure, ensure that there are no thermostat

inputs to the control and all time delays have expired. Turn on setup

switch SW1-6, see Fig. 35..

NOTE: The component test feature will not operate if the control is

receiving any thermostat signals or until all time delays have expired.

The component test sequence is as follows:

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

a. The furnace control CPU turns the inducer motor ON at

high-heat speed and keeps it ON through step c.

b. After waiting 10 seconds the furnace control CPU turns the hot

surface igniter ON for 15 seconds, then OFF.

c. The furnace control CPU then turns the blower motor BLWM on

at mid-range airflow for 15 seconds, then OFF.

d. After shutting the blower motor OFF the furnace control CPU

switches the inducer to low-heat speed for 10 seconds, then OFF.

NOTE: The EAC terminals are energized when the blower is operating.

After the component test is completed, 1 or more status codes (11, 25 or

41) will show. See component test section or Service Label (Fig. 52) for

explanation of status codes.

NOTE: To repeat component test, turn setup switch SW1-6 to OFF and

then back ON.

Wiring Diagram

Refer to Fig. 56 for wiring diagram.

Troubleshooting

Refer to the service label (see Fig. 52) for some troubleshooting

information. Also, the Troubleshooting Guide (see Fig. 57) can be a

useful tool in isolating furnace operation problems. Beginning with the

word “Start,” answer each question and follow the appropriate arrow to

the next item. The Guide will help to identify the problem or failed

component. After replacing any component, verify correct operation

sequence.

WIRING DIAGRAM

A210194

Fig. 56 – Wiring Diagram

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

TROUBLESHOOTING GUIDE

A02108A

Is AMBER LED status light blinking ON/OFF

slowly with a combination of short and

long flashes?

Is AMBER LED status

light blinking

rapidly w

ithout a pause?

Is AMBER LED status

light on?

Determine status code. The status code is

a 2 digit number with the first digit determined

by the num

ber of shor

t flashes and the

second digit by the number of long flashes?

Go to section below for the status code

that was flashed.

YES

To recall previous status codes disconnect

the R thermostat connection, reset power,

and put setup switch SW

1-1

in the ON

position. The AM

BER LED w

ill flash the

status codes in the order of occurrence.

Record status codes until status code #11

flashes (1 short and 1 long flash). After status

code #11 flashes the status codes will repeat.

Status codes are erased after 72 hours or

can be m

nually erased by putting setup

witch SW

1-1

in the O

N position and

jumpering R, W/W1, and Y/Y2 simultaneousl

until status code #11 is flashed. When done

put setup switch SW1-1 in the O

FF posi

tion.

Check for correct line voltage polarity.

If units are twinned, check for proper

low-voltage (24V) transformer phasing.

Was there a previous status code other

than #11?

Is door switch closed?

Is there 115V going to switch?

Replace door switch.

Replace transformer.

Does the control respond to W/W1, W2, Y1,

Y/Y2, and G (24V) thermostat signals?

Replace furnace control.

Is 24V present at W/W1, W2, Y1, Y/Y2 or G

thermostat terminals on the

fur

nace control?

YES

Replace furnace control.

Is there 24V at SEC-1 and SEC-2?

Is there 115V at L1 and L2?

YES

Run system

through a

w-heat, high-heat,

or cooling cycle to check operation. Status

codes are erased after 72 hours or can be

manually erase

d b

y putting setup switch

SW1-1 in the ON position and jumpering R,

W/W1, and Y/Y2 sim

ultaneou

sly until status

code #11 is flashed.

YES

Close circuit break

er and go back to START.

Check for continuity in wire from

circui

breaker to furnace.

Is circuit breaker closed?

Is door switch closed?

Check room thermostat or

interconnecting cable.

YES

The thermostat is not com

patib

le with the

furnace control. Either install a ballast resistor,

connect the Com24V

thermostat terminal to

the thermostat, or replace the thermostat.

Does the problem repeat w

hen using

a jumper wire?

Disconnect all the thermostat wires from the

furnace control.

START

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

A02108B

11 NO PREVIOUS CODE – Status codes

are erased after 72 hours or can be

manually erased by putting setup switch

SW1-1 in the ON position and jumpering

R, W/W1, and Y/Y2 simultaneously until

status code #11 is flashed. Run system

through a low-heat, high-heat, or cooling

cycle to check system.

12 BLOWER ON AFTER POWER UP –

(115V OR 24V) – Normal operation.

Blower runs for 90 seconds, if unit is

powered up during a call for heat (R-

W/W1 closed) or when (R-W/W1 opens)

during the blower on-delay period.

13 LIMIT CIRCUIT LOCKOUT – Lockout

occurs if the limit, draft safeguard, flame

rollout, or blocked vent switch* (if used)

is open longer than 3 minutes or 10

successive limit trips occurred during

high-heat. Control will auto-reset after 3

hours. See code 33.

14 IGNITION LOCKOUT – System failed to

ignite gas and prove flame in 4 attempts.

Control will auto-reset after 3 hours.

See status code 34.

15 BLOWER MOTOR LOCKOUT – Indicates

the blower failed to reach 250 RPM or

the blower failed to communicate within

30 seconds after being turned ON in two

successive heating cycles. Control will

auto-reset after 3 hours. See code 41.

21 GAS HEATING LOCKOUT – Turn off

power and wait 5 minutes to retry.

Check for:

- Stuck closed gas valve relay on control.

- Miswire or short to gas valve wire.

22 ABNORMAL FLAME-PROVING SIGNAL

Flame is proved while gas valve is de-

energized. Inducer will run until fault is

cleared. Check for:

- Stuck open or leaky gas valve.

23 PRESSURE SWITCH DID NOT OPEN

Check for:

- Obstructed pressure tube.

- Pressure switch stuck closed.

24 SECONDARY VOLTAGE FUSE IS OPEN

Check for:

- Short circuit in secondary voltage

(24V) wiring including thermostat

leads. Disconnect thermostat leads

to isolate short circuit.

32 LOW-HEAT PRESSURE SWITCH DID

NOT CLOSE OR REOPENED – If open

longer than 5 minutes, inducer shuts off

for 15 minutes before retry. If opens

during blower on-delay period, blower will

come on for the selected blower off-delay.

Check for:

- Proper vent sizing.

- Low inducer voltage (115V).

- Low inlet gas pressure (if LGPS used).

- Inadequate combustion air supply.

- Disconnected or obstructed pressure

tubing.

Defective inducer motor.

- Defective pressure switch.

- Excessive wind.

- Restricted vent.

33 LIMIT CIRCUIT FAULT – Indicates the

limit, draft safeguard, flame rollout, or

blocked vent switch* (if used) is open or

the furnace is operating in high-heat only

mode due to 2 successive low-heat limit

trips. Blower will run for 4 min. or until

open switch remakes whichever is longer.

If open longer than 3 min., code changes

to lockout #13. If open less than 3 min.

status code #33 continues to flash until

blower shuts off. Flame rollout switch and

BVSS requires manual reset. Check for:

-Dirty filter or restricted duct system.

- Loose blower wheel.

- Defective switch or connections.

- Inadequate combustion air supply

(flame rollout switch open).

- Restricted vent.

- Proper vent sizing.

- Excessive wind.

34 IGNITION PROVING FAILURE – If flame

is not sensed during the trial for ignition

period, the control will repeat the ignition

sequence 3 more times before lockout

#14 occurs. If flame signal is lost during

the blower on-delay period, blower will

come on for the selected blower off-delay.

Check the following items first before

proceeding to the next step.

- Gas valve turned off.

- Manual shut-off valve.

- Green/Yellow wire MUST be connected

to furnace sheet metal.

- Flame sensor must not be grounded.

To determine whether the problem is in

the gas valve, igniter, or flame sensor the

system can be operated in component

test mode. To check the igniter remove

the R thermostat connection from the

control, reset power, and put setup switch

SW1-6 in the ON position to start the

component test. Does the igniter glow

orange/white by the end of the 15 second

warm-up period?

43 LOW-HEAT PRESSURE SWITCH OPEN

WHILE HIGH-HEAT PRESSURE

SWITCH IS CLOSED - Check for:

-Low-heat pressure switch stuck open.

- Disconnected or obstructed pressure

tube.

- Miswired pressure switches.

-Low inlet gas pressure (if LGPS used).

Unplug igniter harness from control and

repeat component test by

turning setup s

witch

SW1-6 OFF and then back ON. Check for

115V between pin 3 and NEUTRAL-L2 on

the control. Was 115V present for the 15

second period?

Reconnect the R thermostat lead and set

thermostat to call for heat. Connect voltmeter

across gas valve connections. Does gas

valve receive 24V?

Does gas valve open and allow gas to flow?

Do the main burners ignite?

Do the main burners stay on?

Repeat call for heat and check flame sensor

current during trial for ignition period. Is the

DC microamps below 0.5?

Clean flame sensor with fine steel wool and

recheck current. Nominal current is 4.0 to

6.0 microamps.

Is current near typical value?

Will main burners ignite and stay on?

Fixed.

45 CONTROL CIRCUITRY LOCKOUT

Auto-reset after 1 hour lockout due to:

- Flame circuit failure.

- Gas valve relay stuck open.

- Software check error.

Reset power to clear lockout.

Replace control if code repeats.

Replace furnace control.

Check for continuity in the harness and

igniter. Replace defective component.

YES

Check connections

. If OK, replace control.

Check that all gas valves are turned on.

Replace valve.

Check for:

- Inadequate flame carryover or rough

ignition.

-Low inlet gas pressure.

-Proper firing rate.

-Blocked or incorrect carry- over gap.

(.045” nominal)

Allow blower to come on and repeat test

to check for intermittent operation.

Check connections and retry. If current is

near typical value (4.0-6.0 nominal) and

burners will not stay on, repeat check in high-

heat. If burners will still not stay on replace

control. If burners operate in high-heat then

switch to low-heat,check manifold pressure.

If OK, check burner carryover and flame

sensor location.

Replace electrode.

Replace furnace control.

YES

* Blocked vent switch used in C

himn

ey Adapter Kit

YES

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

A02108C

Fig. 57 – Troubleshooting Guide

25 INVALID MODEL SELECTION OR

SETUP

ERROR – If status code 25 only

flashes 4 tim

es on po

wer-up the control

is missing its m

odel plug

PL4 and is

defaulting to

the model

selection sto

red

in memor

y. If statu

s code 25 fla

shes

contin

uously it could ind

icate any of the

following:

- Model p

lug PL4 is m

issing

and there

is no valid m

odel stored in per

manent

memory. This will happen if you forget

to install the m

odel plug P

L4 on a

service replace

ment contro

-T

hermostat ca

ll with SW1-1 ON.

-Thermostat ca

ll with SW1-6 ON.

-SW1-1 and S

W1-6 both O

31 HIGH-HEA

T PRESSURE SWITCH OR

RELAY DID NO

T CLOSE OR

REOPENED - Chec

k for:

-C

ontrol relay may be d

ective.

- Gas valve is mis

wired.

-See status code 3

41 BLOWER MOTOR FAULT – Indicates the

blo

wer failed to reach 2

50 RPM or th

blower failed to com

municate w

thin the

prescribed tim

e limits

. Thirty seconds

after being tu

ned ON or ten seco

nds

during steady-state operation. Turn power

off and check the following item

s first

before proceed

ing to the

xt step.

-Rubbing blower wheel.

-Loose blower wheel.

-Wiring from

fur

nace control to b

lower

motor.

Remo

e the R

ther

mostat conn

ection

from the furnace control, disconnect both

connectors fro

m the b

lower motor P

L13

and PL14.

Does the blower wheel tur

freely?

Replace

the b

lower control m

odule at

tached

to the blower motor

. Follow the in

structions

with the blower control m

odule to

make sure

the entire blower motor does not n

ed to be

replaced.

You have an open w

ire or bad ter

minal on the

BLUE wire betwe

en the furnace con

trol and

the blo

wer motor

Replace the fu

nace control.

Connect a D

C v

oltmeter across PL3-4 B

(+) and

PL3-2

GREEN (-).

Does the

oltage

fluctuate

as de

scribed two steps

back?

Does the voltage fluctuate as described in the

previous ste

Replace the blower control m

odule atta

ched

to the blower motor. Follow the instructions

with the blower control m

odule to mak

e sure

the

entire

wer motor does

not need to be

replaced.

Turn power back on. Is there

115V

AC at

PL14-5 and P

L14-4?

Is there 12-VDC

at PL13-7 RED (+) and PL13-

1 GREEN (-)?

Is there 12-V

DC at PL3-

1 RED (+) and P

L3-

2 GREEN (-)?

Replace

the fur

nace control.

Is there 5-VDC a

t PL13-16 YELLOW (+) and

PL13-1

GREEN (-)?

The voltage just m

easured

should be v

stable and

should not flu

ctuate m

ore tha

.02-VDC

. If the

voltage fluctuates more than

this get a diff

erent voltmeter before

proceeding.

Turn power off, reconnect PL13 and PL14

the blower motor

, then tur

n power back on.

Connect a D

C v

oltmeter acro

ss PL3-3

YELLOW (+) and

PL3-2 G

REEN (-).

Does

the voltage

fluctuat

e more tha

n it

did in the

pre

vious step?

Turn power off, disconnect P

L13 and PL14

from the blower motor, then turn power back

on. Connect a D

voltmeter a

cross PL1

16 BLUE (+) an

d PL13-1 G

REE

N (-). The

voltage sho

uld be

near 0-VDC b

ut it wil

fluctuate briefly several times a second.

you have an analog voltmeter the

needle will

briefly go high several times a second. If you

have a dig

ital v

oltmeter w

ith

a bar graph it

will sho

w a large chan

in magnitude on

the bar graph several tim

a second.

If you

have a standard digital voltmeter

it will show

a brief fluctuation in voltage and the

magnitude m

y vary dep

ending on th

voltmeter used.

Yo u have an open w

ire or b

d terminal on

either the B

CK or WHITE po

wer leads

between the furnace contro

l and the b

lower

motor. If you have a power choke disconnect

it and chec

k continuity.

You have an open

wire or ba

d terminal on

either the R

ED or GREEN wire between

furnace contro

l and the b

wer motor

Is there 5-V

DC at PL3-3

YELLO

W (+) and

PL3-2 GREEN (-)?

You have an open wire or bad terminal on the

YELLOW wire between the fur

nace control

and the blower motor

YES

A Carrier Company

Edition Date: 08/21

Catalog No: II880TA-02 REV A

Replaces: II880TA-02

880TA/881TA: Installation, Start–Up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

PARTS REPLACEMENT INFORMATION GUIDE

CASING GROUP

Outer door

Blower door

Top filler plate

Bottom filler plate

Bottom enclosure

ELECTRICAL GROUP

Control bracket

Junction box

Limit switch(es)

Circuit board

Door switch

Transformer

Wiring harness 115v

Wiring harness 24v

BLOWER GROUP

Blower housing

Blower cutoff

Blower motor

Blower wheel grommet

GAS CONTROL GROUP

Manifold

Burner assembly

Orifice

Flame sensor

Hot surface igniter

Gas valve

Manual reset limit switches

Burner support assembly

HEAT EXCHANGER GROUP

Heat exchanger cell

Cell panel

Lox NOx baffle (California models only)

INDUCER GROUP

Housing assembly

Pressure switch

Inducer motor

Inducer wheel

Vent elbow assembly

Draft safeguard switch

Power choke (where used)

TO OBTAIN INFORMATION ON PARTS: Consult your installing dealer or classified section of your local telephone directory under “Heating

Equipment” or “Air Conditioning Contractors and Systems” headings for dealer listing by brand name or contact:

BRYANT HEATING & COOLING SYSTEMS

Consumer Relations Department

P.O. Box 4952

Syracuse, New York 13221-4952

1-800-428-4326

EXAMPLE OF MODEL NUMBER

TRAINING

My Learning Center is your central location for professional residential HVAC training resources that help strengthen careers and businesses. We

believe in providing high quality learning experiences both online and in the classroom.

Access My Learning Center with your HVACpartners credentials at www.mlctraining.com.

Please contact us a mylearning@carrier.com with questions.

MODEL

COOLING

CAPACITY

HEATING

CAPACITY

MOTOR WIDTH VOLTAGE

FEATURES/

MINOR SERIES

880TA 36 045 E 17 A -A

FIRE, EXPLOSION, ELECTRICAL SHOCK AND CARBON MONOXIDE POISONING HAZARD

Failure to follow this warning could result in dangerous operation, personal injury, death or property damage.

Improper installation, adjustment, alteration, service, or maintenance can cause personal injury, property damage, or death. Consult a qualified installer, service agency,

or your local gas supplier for information or assistance. The qualified installer or service agency must use only factory-authorized replacement parts, kits, or accessories

when modifying this product.

WARNING