Fujitsu ASU18RLF Service Instructions Manual page 39

Trouble shooting 16
OUTDOOR UNIT Error Method:
Over Current Error
Detective Actuators:
Outdoor unit Main PCB
Compressor
Transistor PCB
Forecast of Cause :
1. Outdoor unit fan operation defective, foreign matter on hear exchanger,
2. Main PCB
3. Inverter compressor failure (lock, winding short)
4. Transistor PCB (IPM) failure
Check Point 1 : Check the outdoor unit fan operation, heat exchanger, ambient temperature
No obstructions in air passages?
Heat exchange fins clogged
Outdoor unit fan motor check
Ambient temperature not raised by the effect of other heat sources?
Discharged air not sucked in?
OK OK
Check Point 2: Check Transistor PCB (IPM)
Check IPM. (PARTS INFORMATION 7)
>> If IPM is abnormal, replace Transistor PCB.
OK OK
Check Point 3: Replace Main PCB
If Check Point 1 or 1,2 do not improve the symptom, change Main PCB.
OK OK
Check Point 4: Replace Compressor
If Check Point 3 do not improve the symptom, change Compressor.
Indicate or Display:
Refer to error code table.
Detective details:
"Protection stop by overcurrent generation after inverter compressor start
processing completed'' generated consecutively 10 times.
* The number of generations is reset if the start-up of
the compressor succeeds.
excessive rise of ambient temperature
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