60
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
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.
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
37
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
38
Indoor unit
and outdoor
unit doesnt
match
LP
compressor and Outdoor fan motor cant
work
Indoor unit and outdoor unit doesnt
match
39
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
40
Normal
communica-
tion
41
Defrosting
OFF 3S
and blink
once
(during blinking,
ON 10s and OFF
0.5s)
Defrosting will occur in heating
mode. Compressor will operate
while indoor fan will stop
operation.
Its the normal state
42
Malfunction of
phase current
detection
circuit for
compressor
U1
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
43
Malfunction of
voltage
dropping for
DC bus-bar
U3
During cooling and drying
operation, compressor will stop
while indoor fan will operate;
During heating operation, the
complete unit will stop
Supply voltage is unstable
