Gree GMV5E Series Service Manual page 250

GREE
frequency bands.
Step 2:
Check whether the compressor sounds sharp or rubs. Compare the sound of the faulty compressor
with that of normal ones.
Step 3:
Check whether the electric expansion valves of ODUs and the 4-way valves act, and whether the oil
return pipes and oil balance valves 1 and 2 are normal. Touch the pipelines next to the return capillary
tubes to check whether there is oil flowing.
Check method for each part:
① Electric expansion valve: This valve will reset for each power-on or power-off action. Touch the
valve and you will feel its vibration during the reset action. A crack sound will be heard as well.
GMV5E DC INVERTER VRF UNITS SERVICE MANUAL
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