Gree GMV5 Series Service Manual page 184

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.
③Oil balance 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 compressor drive, namely the IPM module, to see whether it is normal.
1. Disconnect the power supply. Five minutes later, remove the line of the faulty compressor.
2. Set a multimeter to gear diode. As shown in the figure below, put the black test probe to pad P (on the
left of pad U (BL)) and the red test probe to pad U (BL) (make sure the moisture proof tape is removed).
In normal cases, the multimeter should read 0.39±0.3 V. If it is ―0‖ or infinitely great, the IPM module is
faulty.
GMV5 DC INVERTER VRF UNITS SERVICE MANUAL
Oil balance
valve 2
Oil balance
valve 1
D – Connects to exhaust.
Watch out for scald!
Solenoid
valve
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