7. Maintenance
A
G
en
Indoor unit
A
Union
B
Liquid pipe
C
Gas pipe
D
Stop valve
E
Outdoor unit
F
Refrigerant gas cylinder
G
operating valve
10
B
E
C
F
D
M
L
K
H
I
J
Refrigerant gas cylinder for R32 with siphon
H
Refrigerant (liquid)
I
Electronic scale for refrigerant charging
J
Charge hose (for R32)
K
Gauge manifold valve (for R32)
L
Service port
M
Fig. 7-1
7.1. Gas charge (Fig. 7-1)
1. Connect gas cylinder to the service port of stop valve (3-way).
2. Execute air purge of the pipe (or hose) coming from refrigerant gas cylinder.
3. Replenish specified amount of refrigerant, while running the air to water
heat pump for cooling.
Note:
In case of adding refrigerant, comply with the quantity specified for the refrig-
erating cycle.
Caution:
• Do not discharge the refrigerant into the atmosphere.
Take care not to discharge refrigerant into the atmosphere during installa-
tion, reinstallation, or repairs to the refrigerant circuit.
• For additional charging, charge the refrigerant from liquid phase of the gas
cylinder.
If the refrigerant is charged from the gas phase, composition change may
occur in the refrigerant inside the cylinder and the outdoor unit. In this case,
ability of the refrigerating cycle decreases or normal operation can be im-
possible. However, charging the liquid refrigerant all at once may cause the
compressor to be locked. Thus, charge the refrigerant slowly.
To maintain the high pressure of the gas cylinder, warm the gas cylinder with warm
water (under 40°C) during cold season. But never use naked fire or steam.