Gree GWH12UB-K3DNA4F Service Manual page 77

6. Diagnosis for compressor synchronism (AP1 below is control board of outdoor unit)
Main detection point:
● If the system pressure is over-high?
● If the work voltage is over-low?
Malfunction diagnosis process:
Synchronism after
energize the unit
and start it
No
If the stop time of
compressor is more than
If the compressor wire COMP(UVW) is well
connected, the connection sequence
forwards to clockwise direction?
No
Connect
wire well
Replace
control board
Yes
malfunction?
Replace
compressor
End
74
3min
Yes
Yes
AP1
Remove
No
Synchronism
occurred during
operation
If the outdoor fan works
No
normally?
Yes
If the radiating of unit is
Yes
well?
No
If the input voltage of unit
N
No
is normal?
Yes
If the refrigerant is too
Yes
much?
No
Replace
control board
AP1
Remove
malfunction?
Yes
No
Replace
compressor
End
Check if the fan
Replace fan
terminal OFAN is
capacitor C1
connected well
Replace
Improve the radiating
outdoor fan
of unit (clean heat
exchanger and
increase ventilation)
Start to run until the
power resume normal
voltage
Charge the
refrigerant with
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