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3-22
SM-18001-rev.1
TROUBLESHOOTING
O.U. PCB: Outdoor Unit PCB
I.U. PCB: Indoor Unit PCB
(
)
Is LED3 (yellow)
on I.U. PCB ON?
Is LED3 (yellow) on
I.U. PCB flashing more
than once in 10 seconds.
Yes
Yes
Faulty O.U. PCB.
Set it correctly.
Faulty I.U. PCB.
Faulty I.U. PCB.
Check wiring between
outdoor unit and indoor
units or fuse (EF) for
I.U./O.U. PCB.
No
Yes
No
Does Alarm occur with
all indoor units?
Yes
No
Check other indoor units.
No
No
Is LED3 (yellow)
ON even if connector
CN2 on I.U. PCB
is removed?
Yes
Yes
Indoor
Unit
Does refrigerant system
No. setting between
O.U. and I.U correspond?
O.U.: DSW4 and RSW1
I.U.: DSW5 and RSW2
Is LED1 (red) on
Change-Over Box
PCB ON?
Is LED3 (green) on
Change-Over Box
PCB ON?
Yes
No
No
Check Change-Over
Box wiring.
Check wiring between
outdoor unit and indoor
units.
No
Is LED2 (yellow) on
Change-Over Box PCB
flashing more than
once in 10 seconds?
No
Replace fuse.
Check other
Change-Over Boxes.
Yes
Is the fuse for
Change-Over Box
PCB blown?
Yes
Is voltage between
"L1" and "N" of PCN1
on Change-Over Box
PCB 208 or 230V?
Faulty Change-Over
Box PCB.
No
Change-Over
Box
(In Case
of Heat
Recovery
System)
Yes
Summary of Contents for CIDH018B21S
Page 2: ......
Page 10: ...viii SM 18001 rev 1...
Page 15: ...SM 18001 rev 1 1 1 INSTALLATION 1 Installation...
Page 19: ...SM 18001 rev 1 2 1 OPERATION 2 Operation...
Page 22: ......
Page 23: ...SM 18001 rev 1 3 1 TROUBLESHOOTING 3 Troubleshooting...
Page 75: ...MAINTENANCE SM 18001 rev 1 4 1 4 Maintenance...
Page 130: ......
Page 172: ......
Page 173: ...SM 18001 rev 1 6 1 FIELD WORK INSTRUCTIONS 6 Field Work Instructions...
Page 182: ...6 10 SM 18001 rev 1 FIELD WORK INSTRUCTIONS 6 8 Mollier Chart for R410A f t 3 l b...
Page 183: ...SERVICE PARTS LIST SM 18001 rev 1 7 1 7 Service Parts List...
Page 185: ......
Page 186: ...2018 Johnson Controls Inc SM 18001 rev 1 Code No LIT 12013047 Revised February 2019...