Fujitsu AG * V12LAC Series, Service Instruction

Page: 47 / 89

Self - diagnosis function and Checking points
0.5 sec
2 times
When the indoor unit does not receive the signal for 10 consecutive seconds during the operation
>Permanent stop after 30 seconds.
The outdoor unit does not receive the signal for 10 consecutive seconds from the time when the power relay was ON.
>Outdoor unit stops.
OFF OFF
OFF
OFF
OFF
OFF
OFF
OFF
07
-0
3
Serial forward transfer
error
during the operation
Serial forward transfer
error
at starting up operation
Serial reverse transfer
error
during the operation
Serial reverse transfer
error
at starting up operation
At the start up, the indoor unit does not receive the signal for 10 consecutive seconds from the time when the power relay was ON.
>Permanent stop after 30 seconds.
[Diagnosis Point]
Check the indoor /outdoor cable connection (in order). If the cable wiring is not abnormal, measure the voltage of the outdoor
unit terminals and diagnose the defective location.
(Refer to the after mentioned [Serial Signal Diagnosis] for the voltage measuring method and diagnosis method.)
[Diagnosis Point]
Check the indoor /outdoor cable connection (in order). If the cable wiring is not abnormal, measure the voltage of the outdoor
unit terminals and diagnose the defective location.
(Refer to the after mentioned [Serial Signal Diagnosis] for the voltage measuring method and diagnosis method.)
[Diagnosis Point]
Check the indoor /outdoor cable connection (in order). If the cable wiring is not abnormal, measure the voltage of the outdoor
unit terminals and diagnose the defective location.
(Refer to the after mentioned [Serial Signal Diagnosis] for the voltage measuring method and diagnosis method.)
When the outdoor unit does not receive the signal for 10 consecutive seconds during the operation > Outdoor unit stops.
[Diagnosis Point]
Check the indoor /outdoor cable connection (in order). If the cable wiring is not abnormal, measure the voltage of the outdoor
unit terminals and diagnose the defective location.
(Refer to the after mentioned [Serial Signal Diagnosis] for the voltage measuring method and diagnosis method.)
The room temperature thermistor detective a abnormai temperature when the power was turned on.
> Remote control does not operate.
[Diagnosis Point]
Check thermistor resistance value (Refer to "Themistor characteristics table").
Controller PCB defective.
The detection value of the indoor heat exchanger thermistor is either open or shoted when the power is ON.
> Remote control dose not operate.
[Diagnosis Point]
Check thermistor resistance value (Refer to "Themistor characteristics table").
Controller PCB defective.
Room temperature
thermistor defective
Indoor heat exchanger
thermistor error
0.5 sec
3 times
0.5 sec
4 times
0.5 sec
5 times
Wired remote controller
error
0.5 sec
8 times
0.5 sec
2 times
0.5 sec
3 times
0.5 sec
2 times
When the communication is cut off longer than 1 minutes upon connection.
> Compressor , Outdoor fan : OFF
(If the communication becames normal, they automatically resume operation.
[Diagnosis Point]
Check wiring
Controller PCB failure
01
01
13
13
00
02
04
Error Indication
Operation
(RED)
Timer
(GREEN)
10°C HEAT
(ORANGE)
Error
(Protection)
Diagnosis Method
Wired remote
controller