Fujitsu AOUH18LPAS1, Service Manual

Page: 49 / 169

2-9. E: 51. Indoor unit fan motor error (Indoor unit)
Indicator Indoor unit
Operation indicator 5 time flash
Timer indicator 1 time flash
Economy indicator Continuous flash
Error code E: 51
Detective actuator Indoor unit
main PCB When the actual rotation number of the indoor unit fan
motor is below 1/3 of the target rotation number
continuously for more than 56 seconds.
Fan motor
Forecast of cause
Fan rotation failure
Fan motor winding open
Motor protection by surrounding temperature rise
Control PCB failure
Indoor unit fan motor failure
Check point 1. Check rotation of fan
Rotate the fan by hand when operation is off. (Check if fan is caught, dropped off or locked motor)
→ If fan or bearing is abnormal, replace it.
↓
Check point 2. Check ambient temperature around motor
Check excessively high temperature around the motor. (If there is any surrounding equipment that
causes heat)
→ Upon the temperature coming down, restart operation.
↓
Check point 3. Check indoor unit fan motor
Check Indoor unit fan motor. (Refer to indoor unit fan motor in "Service parts information" on page
03-49.)
→ If Indoor unit fan motor is abnormal, replace Indoor unit fan motor.
↓
Check point 4. Replace main PCB
If Check Point 1 to 3 do not improve the symptom, replace main PCB.
↓
End
2-9. E: 51. Indoor unit fan motor error (Indoor unit)
- (03-13) -
2. Troubleshooting with error code
TROUBLESHOOTING TROUBLESHOOTING