60
Installation and Maintenance
Service Manual
No. Malfunction Name
Display Method of 
Indoor Unit
A/C status Possible Causes 
Dual-8 Code
Display
28
Charging
malfunction of capacitor PU
During cooling and drying operation, compressor 
will stop while indoor fan will operate;
During heating operation, the complete unit will 
stop
Refer to the part three—charging malfunction 
analysis of capacitor
29
Malfunction of module
temperature sensor circuit
P7
During cooling and drying operation, compressor 
will stop while indoor fan will operate;
During heating operation, the complete unit will 
stop
Replace outdoor control panel AP1
30
Module high temperature
protection
P8
During cooling operation, compressor will stop 
while indoor fan will operate; During heating 
operation, the complete unit will stop
After the complete unit is de-energized for 
20mins, check whether the thermal grease on 
IPM Module  of outdoor control panel AP1 is 
sufcient and whether the radiator is inserted 
tightly. If it's no use, please replace control panel 
AP1.
31
Overload protection for
compressor
H3
During cooling and drying operation, compressor 
will stop while indoor fan will operate;
During heating operation, the complete unit will 
stop operation.
1. Wiring terminal OVC-COMP is loosened. In 
normal state, the resistance for this terminal 
should
be less than 1ohm. 
2.Refer to the malfunction analysis ( discharge 
protection, overload)
32 IPM protection H5
During cooling and drying operation, compressor 
will stop while indoor fan will operate;
During heating operation, the complete unit will 
stop operation.
Refer to the malfunction analysis (IPM protection, 
loss of synchronism protection and overcurrent 
protection of phase current for compressor.
33
Module temperature is too 
high
P8
During cooling and drying operation, compressor 
and outdoor fan stop while indoor fan operates. 
During heating operation, all loads stop.
Radiating grease on IPM module of
outdoor unit main board is not enough;
screws have not been xed tightly;
Hardware malfunction of outdoor unit main board;
34
Internal motor (fan motor) 
do not operate
H6
Internal fan motor, external fan motor, compressor 
and electric heater stop operation,guide louver 
stops at present location.
1. Bad contact of DC motor feedback terminal.
2. Bad contact of DC motor control end.
3. Fan motor is stalling.
4. Motor malfunction.
5. Malfunction of mainboard revdetecting circuit.
35
Desynchro-nizing of 
compressor
H7
During cooling and drying operation, compressor 
will stop while indoor fan will operate;
During heating operation, the complete unit will 
stop operation.
Refer to the malfunction analysis (IPM protection, 
loss of synchronism protection and overcurrent 
protection of phase current for compressor.
36
Outdoor DC fan motor 
malfunction
L3
Outdoor DC fan motor malfunction lead to 
compressor stop operation, 
DC fan motor malfunction or system blocked or 
the connector loosed