Gree GUHD09NK3FO Service Manual page 74

3.1.7 Vacuum and Gas Leakage Inspection
3.1.7.1 Vacuum
(1).
(2). Connect the hose at the low pressure side of the manifold valve assembly to the service port of the unit's
gas valve, and meanwhile the gas and liquid valves should be kept closed in case of refrigerant leak.
(3). Connect the hose used for evacuation to the vacuum pump.
(4). Open the switch at the lower pressure side of the manifold valve assembly and start the vacuum
pump. Meanwhile, the switch at the high pressure side of the manifold valve assembly should be kept closed,
otherwise evacuation would fail.
indicates there is leak somewhere. Then, close the switch fully and then stop the vacuum pump.
(7). Slightly open the liquid valve and let some refrigerant go to the connection pipe to balance the pressure
inside and outside of the connection pipe, so that air will not come into the connection pipe when removing the
hose. Note that the gas and liquid valve can be opened fully only after the manifold valve assembly is removed.
(8). Place back the caps of the liquid valve, gas valve and also the service port.
Note:
evacuation, it is available to connect two hoses of the manifold valve assembly to two service ports to quicken
the evacuating speed.
3.1.7.2 Additional Charge
gauge manifold
Hose with the valve pin
Item
Model
U-Match Series DC
Inverter Service Manual
pipe
Low pressure gauge
High pressure gauge
Gauge manifold kit
pipe
Service port
Vacuum pump
VAC valve
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