Hitachi YUTAKI S COMBI Series User Manual

6.1.2 Precautions in the event of gas refrigerant leaks
The installers and those responsible for drafting the specications are obliged to comply with local safety codes and regulations in
the case of refrigerant leakage.
! CAUTION
• Check for refrigerant leakage in detail. If a large refrigerant leakage occurred, it would cause difculty with breathing or harmful gases would occur
if a re were in the room.
• If the are nut is tightened too hard, it may crack over time and cause refrigerant leakage.

Maximum permitted concentration of HFCs
The refrigerant R410A (charged in the outdoor unit) and the refrigerant R134a (in case of YUTAKI S80 indoor unit) are incombustible
and non-toxic gases. However, if leakage occurs and gas lls a room, it may cause suffocation.
The maximum permissible concentration of HFC gas according to EN378-1 is:
Refrigerant Maximum permissible concentration (kg/m
3
)
R410A 0.44
R134a 0.25
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)
2 HP 3.2
2.5 HP 3.5
3 HP 3.9
4 HP 7.5
5/6 HP 7.8
YUTAKI S
8 HP 11.4
10 HP 12.1
YUTAKI S80 4-6 HP 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.
REFRIGERANT AND WATER PIPING
PMML0335A rev.1 - 04/2016
86

Hitachi YUTAKI S COMBI Series Specifications

General

Brand	Hitachi
Model	YUTAKI S COMBI Series
Category	Heat Pump
Language	English