Published by the Daikin Product Marketing Department
(Daikin’s products are subject to continuous improvements. Daikin reserves the right to modify product design, specification and information in this document
without notice and without incurring any obligation.)
Page 5 of 17
“A high-probability system is any
system in which the basic design,
or the location of components, is
such that a leakage of refrigerant
from a failed connection, seal, or
component will enter the occupied
space…”
Reprinted with permission.
©ASHRAE, www.ashrae.org
2010 ANSI/ASHRAE Standard 15
“The terms “authority having
jurisdiction (AHJ)” and
“jurisdictional authority” used
herein refer to the organization or
individual responsible for
enforcing the requirements of this
standard.”
Reprinted with permission.
©ASHRAE, www.ashrae.org
2010 ANSI/ASHRAE Standard 15
“refrigerant concentration limit
(RCL): the refrigerant
concentration limit, in air,
determined in accordance with this
standard and intended to reduce
the risks of acute toxicity,
asphyxiation, and flammability
hazards in normally occupied,
enclosed spaces.”
Reprinted with permission.
©ASHRAE, www.ashrae.org
2010 ANSI/ASHRAE Standard 34
“Listed equipment containing not
more than 6.6 lb(3 kg) of
refrigerant, regardless of its
refrigerant safety classification, is
exempt from Section 7.2 provided
the equipment is installed in
accordance with the listing and
with the manufacturer’s
installation instructions.”
Reprinted with permission.
©ASHRAE, www.ashrae.org
2010 ANSI/ASHRAE Standard 15
Daikin VRV systems use refrigerant 410A with minimal potential safety risks compared to most
other DX-type HVAC systems. The safety classification of R410A
in Standard 34 is group 1 (meaning non-toxic and non-flammable),
it has no ozone depletion potential and it meets the stringent
mandates of both the Montreal Protocol and the U.S.
Environmental Protection Agency. However, due to the ability to
displace oxygen, Addendum L to ASHRAE Standard 34-2010
has established the maximum RCL to 26 lbs/1000 ft
3
of room
volume for occupied spaces.
For Institutional Occupancies, the limit is reduced to 50% (13
lbs/1000 ft
3
).
For smaller systems with less than 6.6 lbs of total refrigerant charge, the 26 lbs/1000 ft³ limit
described above does not apply, regardless of refrigerant safety
classification, if the system is installed according to the listing and
manufacturer’s instructions.
Since the indoor unit fan coils are in direct contact with the air
being distributed, a VRV system is classified as a Direct System
according to Standard 15.
By definition, a Direct System is also classified as a High
Probability system, meaning that a leak of refrigerant can
potentially enter into occupied space.
The information in this document is intended to provide guidance
to specifying and designing a VRV system while applying
ASHRAE safety Standard 15. However, since many of the
attributes of a modern cooling/heating technology, such as VRV,
are not specifically addressed in Standard 15, there might be
variations in how the “authority having jurisdiction” (AHJ)
interprets compliance requirements to Standard 15 between
jurisdictions.
Therefore, it is good practice to review the local code and work
with the local AHJ when designing a system.