Fujitsu AO*G09LTCN, Service Instructions Manual

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Trouble shooting 21
Forecast of Cause:
OK OK
Indoor Unit - No Power
1. Power supply failure 2. External cause
3. Electrical components defective
Check Point 1 : Check Installation Condition
Isn’t the breaker down?
Check loose or removed connection cable.
>>If abnormal condition is found, correct it by referring
to Installation Manual or Data & Technical Manual.
Check Point 2 : Check external cause at Indoor and Outdoor (Voltage drop or Noise)
Instant drop ----- Check if there is a large load electric apparatus in the same circuit.
Momentary power failure ----- Check if there is a defective contact or leak current in
the power supply circuit.
Noise ----- Check if there is any equipment causing harmonic wave near electric line.
(Neon bulb or electric equipment that may cause harmonic wave)
Check the complete insulation of grounding.
02-25
2-3 TROUBLE SHOOTING WITH NO ERROR CODE
Check Point 3 : Check Electrical Components
YES YES
NO
Check the voltage of power supply.
>> Check if AC207 - 253V appears at Outdoor Unit Terminal L - N.
Check Fuse in Main PCB.
>> If Fuse is open, check if the wiring between Terminal and Main PCB
is loose, and replace Fuse.
Check Varistor in Main PCB.
>> If Varistor is defective, there is a possibility of an abnormal power supply.
Check the correct power supply and replace Varistor.
Upon checking the normal power supply, replace Varistor.
OK