ENGLISH
The minimum volume of a closed room where the system is installed to avoid suffocation in case of leakage is:
System combination
Minimum volume (m
3
)
YUTAKI S / SCOMBI
4HP
7.5
5/6HP
7.8
YUTAKI S
8HP
11.4
10HP
12.1
YUTAKI S80
4-6HP
7.6
The formula used for the calculation of the maximum allowed refrigerant concentration in cases of refrigerant leakage is the
following:
R
— = C
V
R: Total quantity of refrigerant charged (kg)
V: Room volume (m³)
C: Refrigerant concentration
If the room volume is below the minimum value some effective measure must be taken into account after installing to prevent
suffocation is case of leakage.
Countermeasure in the event of possible refrigerant leakage
The room must have the following features to prevent suffocation in case a refrigerant leakage occurs:
1
Provide a shutterless opening which will allow fresh air to circulate into the room.
2
Provide a doorless opening of 0.15% or more of the floor area.
3
There must be a ventilator fan connected to a gas leak detector, with a ventilator capacity of 0.4 m
3
/min or higher per Japanese
refrigeration ton (= compressor displacement volume / (5.7 m
3
/h (R410A) or 14.4 m
3
/h (R134a)) of the air conditioning system
using the refrigerant.
Model
Tonnes
RAS-(4-6)WH(V)NPE
2.27
RAS-8WHNPE
3.16
RAS-10WHNPE
4.11
Model
Tonnes
R410A
R134a
Outdoor unit
RAS-(4-6)WH(V)NPE
2.27
-
Indoor unit
RWH-(4.0-6.0)(V)NF(W)E
-
1.61
?
N O T E
Always take the maximum value between the R410A and R134a.
4
Pay special attention to the place, such as a basement, etc., where the refrigerant can stay, since refrigerant is heavier than air.
Example:
Outdoor unit (RAS-5WHVNPE)
Refrigerant (R410A): 3.4 kg
Gas leak detector
Fan (m
3
/min)
Height 2.5 m
Floor 3.0 m
2
Opening (m
2
)
Indoor unit
(RWM-5.0NE(-W))
R (kg)
V (m³) C (kg/m
3
)
Countermeasure
3.4
7.5
0.46
1.0 m
3
/min fan linked with gas leak
detector or 0.5 m
2
opening
REFRIGERANT AND WATER PIPING
PMML0575 rev.2 - 03/2022
55
