59
Installation and Maintenance
Service Manual
No.
Malfunction
Name
Display Method of Indoor Unit
A/C status
Possible Causes
Dual-8
Code
Display
Indicator Display (during
blinking, ON 0.5s and OFF
0.5s)
operation
Indicator
Cool
Indicator
Heating
Indicator
26
Compressor
intermediate
frequence in
test state
P3
Showing during middle cooling or middle
heating test
27
Overcurrent
protection of
phase
current for
compressor
P5
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.
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
sufficient and whether the radiator is inserted
tightly. If its 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
Malfunction
of zero-cross
detection
circuit
U8
The complete unit stops
1.Power supply is abnormal;
2.Detection circuit of indoor control mainboard
is abnormal.
