GREE U-Match 5 SERIES UNIT SERVICE MANUAL
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Step 5: Open the high pressure gauge valve (Keep the low pressure gauge valve closed). Then charge
refrigerant into the system. Meanwhile, record the weight of refrigerant tank as m2.
Step 6: m1-m2=m. If m equals to the required charging quantity M, close the valve of refrigerant tank at once.
Then move to step 8.
Step 7: If you can
‘t continue to charge refrigerant into the system and the quantity of charged refrigerant is
less than the required charging quantity, then record the current quantity of charged refrigerant:
m=m1-m2
m`=M-m
The remaining charging quantity is: m`=M-m
Step 8: After charging, remove the pressure gauge.
Refrigerant charging when unit is turned on:
Step 1: Close the valve of refrigerant tank. First remove the pressure gauge lines and connect the outdoor
unit to the indoor unit. Then reconnect the pressure gauge lines. Connect the low pressure gauge line to the other
joint of gas valve and connect the high pressure gauge line to the liquid valve. Connect the middle gauge line to
the vacuum pump. Power on the vacuum pump and perform vacuum drying.
Step 2: After vacuum drying, close the high and low pressure gauge valves. Then remove the middle gauge
line from the connector of vacuum pump. Then connect to the refrigerant tank.
Step 3: Loosen the middle gauge line from the connector of pressure gauge to a proper extent and slightly
open the valve of refrigerant tank. Evacuate the middle gauge line. Then tighten up the connector again and
completely open the valve of refrigerant tank at the same time.
Step 4: Turn on the air conditioner and let it run for a while.
Step 5: Open the low pressure gauge valve (Keep the high pressure gauge valve closed). Then charge in the
remaining charging quantity m`.
Step 6: After all required refrigerant is charged in, close the valve of refrigerant tank.
Step 7: Remove the pressure gauge to finish the refrigerant charging work.
Procedure of refrigerant charging
