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TROUBLESHOOTING
“RUN” light flickers and “ALARM” is indicated on the remote control switch.
The unit No., alarm code and the unit code is alternately indicated on the set temperature section,
and the unit No. and alarm code are indicated on the display of the outdoor unit PCB.
This alarm code is indicated when a current value of AC chopper becomes (1) less than 0.5A when
outdoor unit fan is operating, or (2) more than 2A while outdoor unit fan stops.
Alarm
Code
Abnormality of AC Chopper Circuit Board
(Only for 5 to 20HP & 24, 30HP 380-415/380V 50/60Hz)
Yes
Yes
Yes
No
No
No
Is the connection of
CT5 at outdoor circuit
board (PCB1) right?
Is outdoor unit fan operating
during the indication of
alarm code?
Is the connection of CN13
at outdoor unit circuit board
(PCB1) and CN201 at AC
chopper circuit board right?
No
Abnormality of AC
chopper circuit board
(PCB2).
Yes
Connect CT5 correctly.
Connect correctly.
Yes
Is the connection of S3, R3
at outdoor unit circuit board
(PCB1) or faston of EF9 and
S1, R1 at AC chopper circuit
board right?
Connect correctly.
No
Connect correctly.
No
Connect correctly.
Faulty AC chopper.
Replace the AC chopper.
Replace fuse.
Abnormality of CT5.
Yes
Is the fuse of EF9 melted?
Yes
Is outdoor unit fan operated
for more than 2 seconds
when the unit is restarted?
Is the connection of MAIN1,
COM1, SUB1 at AC chopper
circuit board right?
Yes
Is the connection of relay
connector CN1 for outdoor
fan motor right?
No
No