Gree GWH12UB-K3DNA4F Service Manual page 76

Service Manual
5. Diagnosis for failure start up malfunction (AP1 below is control board of outdoor unit)
Main detection point:
● If the compressor wiring is correct?
● If the stop time of compressor is enough?
● If the compressor is damaged?
● If the refrigerant charging is too much?
Malfunction diagnosis process:
Installation and Maintenance
Energize the unit
and start it
If the stop time of compressor
is more than 3min?
Yes
If the compressor wire COMP(UVW) is
well connected and connection sequence
is correct
Yes
If the refrigerant charging is
too much?
Yes
Charge the
refrigerant according
to service manual
Does the unit start
up normally?
No
Replace control board AP1
If malfunction is
removed?
No
Replace the
compressor
End
If the stop time is not enough and the
No
high and low pressure of system is not
balance , please start it after 3min
Improve the connection situation
of control board AP1 and
N
No
compressor COMP, connect it
with wiring diagram
Does the unit start
up normally?
No N
Yes
73