43
Installation and Maintenance
Service Manual
No.
Malfunction
Name
Display Method of
Indoor Unit
A/C status
Possible Causes
Dual-8
Code
Display
26
Compressor
intermediate
frequence in
test state
P3
Showing during middle cooling or
middle heating test
26
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.
27
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
28
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
29
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.
30
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)
31
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.
32
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 rev
detecting circuit.
