Fujitsu AUXG18KVLA, Service Manual

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2-15. E: 51. Indoor unit fan motor error (Indoor unit)
Indicator
Wired remote
controller
Error code E: 51
Detective actuator Indoor unit
main PCB When the condition that actual frequency of indoor fan is
below 1/3 of target frequency is continued 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
03-57.)
→ 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
2-15. E: 51. Indoor unit fan motor error (Indoor unit)
- (03-22) -
2. Troubleshooting with error code
TROUBLESHOOTING TROUBLESHOOTING