
1-32
TROUBLESHOOTING
Is LED3 (yellow)
on PCB1 ON?
Is DSW5-1P (End
Terminal Resistance)
of PCB(1) ON?
No
Yes
Yes
Yes
Is the voltage
between faston
terminal "R1" and
"N" of PCB1 220V
or 240V?
Is DSW10-1P
(Terminal Resistance)
on PCB1 ON? *1)
Is LED3 (yellow)
on PCB1 flickering
more than once in
10 seconds?
No
Is connector (PCN1,
CN1) for transformer
is loosened?
Is LED1 (red) on
PCB1 ON?
Set it correctly.
No
Remove CN2 of
PCB1. *2)
Yes
Is LED1 (red) on
PCB(1) ON?
Yes
Is LED3 (green) on
PCB(1) ON?
Yes
Connect CN2 of
PCB1.
Yes
Remove CN8 of PCB(1).
To Next Page
Replace fuse.
No
No
No
No
Set it correctly.
Check CH unit wiring.
Yes
Plug PCN1 and CN1
correctly.
Check the fuses of
outdoor unit power
supply.
No
Check wiring between
outdoor unit and indoor
units or fuse (EF3) for
PCB(1).
No
Faulty PCB1
PCB1:
Outdoor Unit Printed Circuit Board
PCB1': Indoor Unit Printed Circuit Board
Outdoor
Unit
No
Is LED3 (yellow)
on PCB(1) flickering
more than once in
10 seconds?
No
No
Is the fuse for
PCB1 melted?
Yes
Yes
No
Is connector (TR,
CN7) for transformer on
PCB(1) is loosened?
Replace fuse.
Check other CH units.
Yes
Plug TR and CN7
correctly.
Is LED3 (green)
still ON after removing
CN9 on PCB(1)?
Yes
Yes
Is the fuse for
PCB(1) melted?
Yes
Yes
Is voltage between
"R1" and "N" of PCN1
on PCB(1) 220V
or 240V
Faulty PCB(1)
No
No
CH
Unit