Fujitsu AO*G24LFLAO*G24LFCC, Service Instruction

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Trouble shooting 2
INDOOR UNIT Error Method:
Detective Actuators: Detective details:
Forecast of Cause:
OK
Indicate or Display:
Refer to error code table.
YES YES
NO
OK
Serial Communication Error
(Serial Forward Transfer Error)
Indoor unit Controller PCB
1. Connection failure 2. External cause 3. Controller PCB failure
Check Point 1-1 : Reset the power and operate
Does error indication reappear?
Check Point 1-2 : Check external cause such as noise
Check if the ground connection is proper.
Check if there is any equipment that causes harmonic wave
near the power cable (Neon light bulb or any electronic
equipment which causes harmonic wave).
Check Point 2 : Check connection
Check any loose or removed connection line of
between indoor unit and outdoor unit.
>> If there is an abnormal condition, correct it by
referring to Installation Manual or Data &
Technical Manual.
Check connection condition in control unit.
(If there is loose connector, open cable or mis-wiring)
Check Point 3 : Check the voltage of power supply
Check the voltage of power supply
>> Check if AC216V(AC240V-10%) - 264V(10%) appears
at outdoor unit terminal L - N.
Check Point 4 : Check serial signal (Forward transfer signal)
Check serial signal (Forward transfer signal)
>> Check if indicated value swings between AC30V and AC130V at outdoor unit terminal 2 - 3.
>> If it is abnormal, replace Controller PCB.
When the outdoor unit cannot properly receive the serial signal from
indoor unit for 10 seconds or more.
02-04
1
2
3
L
N
RED
WHITE
BLACK
BLACK
WHITE
+
-