43
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
34
System is
abnormal
H4
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
(overload, high temperature
resistant)
35
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.
36
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.
37
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.
38
PFC
protection
HC
During cooling and drying
operation, compressor will stop
while indoor fan will operate;
During heating operation, the
complete unit will stop
operation.
Replace outdoor control panel
AP1 or Reactor
39
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
40
power
protection
L9
compressor stop operation and
Outdoor fan motor will stop
30s latter , 3 minutes latter
fan motor and compressor will
restart
To protect the electronical
components when detect high
power
41
Indoor unit
and outdoor
unit doesn't
match
LP
compressor and Outdoor fan
motor can’t work
Indoor unit and outdoor unit doesn't
match
42
Failure start-
up
LC
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
