Gree U-MATCH B Series, Руководство пользователя

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U-MATCH SERIES DC INVERTER AIR CONDITIONERS SERVICE MANUAL
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3.1.6 Heat Insulation on the Pipe Joints (Indoor Side Only)
Stick coupler heat insulation (large and small) to the place where connecting pipes.
Figure 3-2-3
3.1.7 Vacuum and Gas Leakage Inspection
CAUTION!
Do not purge the air with refrigerants but use a vacuum pump to vacuum the installation! There is no extra refrigerant
in the outdoor unit for air purging!
3.1.7.1 Vacuum
Remove the caps of the liquid valve, gas valve and also the service port.
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.
Connect the hose used for evacuation to the vacuum pump.
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.
The evacuation duration depends on the uni
t‘s capacity, generally, 20 minutes for the 18k units, 30
minutes for the 24/30/36k units, 45 minutes for the 42/48k units. And verify if the pressure gauge at the
low pressure side of the manifold valve assembly reads -1.0MPa (145psig), if not, it indicates there is
leak somewhere. Then, close the switch fully and then stop the vacuum pump.
Wait for some time to see if the system pressure can remain unchanged, 3 minutes for the 18/24k
units, 10 minutes for the 30/36/42/48k units. During this time, the reading of the pressure gauge at the
low pressure side can not be larger than 0.005Mpa (0.72psig).
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.
Place back the caps of the liquid valve, gas valve and also the service port