64
Installation and Maintenance
Service Manual
NO.
Malfunction
Name
Display Method of Indoor Unit
Display Method of Outdoor
Unit
A/C status
Possible Causes
Dual-8
Code
Display
Indicator Display (during
blinking, ON 0.5s and OFF
0.5s)
Indicator has 3 kinds of
display status and during
blinking, ON 0.5s and OFF
0.5s
Operation
Indicator
Cool
Indicator
Heating
Indicator
Yellow
Indicator
Red
Indicator
Green
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
OFF 3S
and blink
8 times
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
OFF 3S
and blink
4 times
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.
