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12
9 IPM malfunction or IGBT over-strong current protection diagnosis and solution (P0)
Error Code
P0
Malfunction decision
conditions
When the voltage signal that IPM send to compressor drive chip
is abnormal, the display LED will show “P0” and AC will turn off.
Supposed causes
Wiring mistake; IPM malfunction; Outdoor fan ass’y faulty
Compressor malfunction; Outdoor PCB faulty
Check the wiring between main PCB
and compressor
Correct the connection or replace
the wires and connectors.
Yes
No
Check the IPM
No
Yes
Replace the IPM board or replace
the main PCB
Check the outdoor fan and the
outdoor unit ventilation
No
Please refer to the solution of
【
Fan
Speed Has Been Out Of Control
】
malfunction
Yes
Check the compressor resistance
values
No
Replace the compressor.
Yes
Replace the outdoor main PCB
Summary of Contents for 38QUS012DS
Page 1: ...SERVICE MANUAL 12 18 24K LIGHT COMMERCIAL ...
Page 5: ...2 PRODUCT LINEUP ...
Page 6: ...3 UNIT MODEL INDENTIFICATION ...
Page 7: ...PART 1 GENERAL INFORMATION 1 1 DUCT ...
Page 9: ...2 INSTALLTION SPACE ...
Page 10: ...3 STATIC PRESSURE ...
Page 11: ...4 STATIC PRESSURE 42QSM012DS ...
Page 12: ...5 STATIC PRESSURE 42QSM018DS ...
Page 13: ...6 STATIC PRESSURE 42QSM024DS ...
Page 18: ...11 5 Screw off the fixing screws to remove the evaporator 1 screw ...
Page 19: ...PART 1 GENERAL INFORMATION 1 2 CASEETTE ...
Page 22: ...3 INSTALLTION SPACE ...
Page 29: ...PART 1 GENERAL INFORMATION 1 3 UNDER CEILING ...
Page 31: ...3 INSTALLTION SPACE ...
Page 37: ...PART 1 GENERAL INFORMATION 1 4 OUTDOOR UNIT ...
Page 44: ...8 compressor on bottom plate 4 Lift the compressor from the base pan assembly ...
Page 45: ...PART 2 ELECTRICAL DIAGRAM ...
Page 46: ...1 WIRING DIAGRAM 42QSM012 18 24DS ...
Page 47: ...2 WIRING DIAGRAM 42QTD012 18DS ...
Page 48: ...3 WIRING DIAGRAM 42QTD024DS ...
Page 49: ...4 WIRING DIAGRAM 42QZL018 24DS ...
Page 50: ...5 WIRING DIAGRAM 38QUS012DS ...
Page 51: ...6 WIRING DIAGRAM 38QUS018DS ...
Page 52: ...7 WIRING DIAGRAM 38QUS024DS ...
Page 53: ...PART 3 TROUBLE SHOOTING ...