Gree Ultra Heat GMV-VQ72W/A-F, Service Manual

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Ultra Heat GMV VRF Technical Service Manual_Heat Recovery Serial MAINTENANCE
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Labels on the 4-way valve and their meanings: D
– connects to exhaust; E – connects to IDU
evaporator; S
– connects to intake of gas separator; C – connects to condenser. When the system is
cooling, the pipe at side C works at high pressure high temperature, the pipes at sides E and S work at
low pressure low temperature; when the system is heating, the pipe at side E works at high pressure
high temperature, the pipes at sides C and S work at low pressure low temperature. The pipe at side D
connects to exhaust and it is always working at high pressure high temperature. When units are starting,
defrosting, or returning oil, the valve will vibrate obviously. DO NOT touch the pipe; or, you may be
scalded.
(3) Oil solenoid valve: This valve can be operated based on its state that is shown through the
monitoring software and actual situation. When this valve is opened, the coil will be heated and lubricant
at both sides of the valve flows.
Step 4: Test the IPM module of compressor drive board and PFC board to see whether it is normal.
1) Disconnect the power supply. Five minutes later, remove the line of the faulty compressor.