Outdoor Unit Check Method - IVT 12KHR-N Service Manual

12KHR-N
5. IPM check method
Turn off the power, let the large capacity electrolytic capacitor (C10) discharge completely, and dismount the IPM. Then, using a tester, check leak
current between C and E.
When using a digital tester, the (+) and (-) tester lead wires in the table must be reversed.
Needle-type tester Normal resistance value
(-) (+)
P N
(several M )
U
V
W
5.1. IPM internal circuit diagram
Connect power cord
to AC outlet.
Check 220-240 VAC
between (1) and (N)
on outdoor unit PWB.
YES
NO
Is LED1 on outdoor
unit flashing?
YES
Using remote control,
operate air conditioner
so that compressor
starts.
Compressor starts up.
Immediately
after startup
YES
Does LED1 indicate
DC overcurrent error?
NO
YES
Does LED1 indicate
rotation error?
NO
Normal

[7] OUTDOOR UNIT CHECK METHOD

After repairing the outdoor unit, conduct the following inspection procedures to make sure that it has been repaired completely. Then, operate the
compressor for a final operation check.
No
(unlit)
Does LED1 remain lit?
YES
Serial signal error.
FUSE and+12 V, +15 V,
Check inter-unit wiring.
Check indoor and
outdoor unit PWBs.
Replace outdoor unit
PWB.
Check compressor.
2/3-way valve closed.
Refrigerant shortage.
Replace outdoor unit PWB.
NO
Replace compressor.
Needle-type tester
(-)
U
V
W
Values in ( ) are for digital tester.
NO
Check 320 VDC between
pins IPM (20) and (24)?
YES
NO
+18V on PWB
YES
(LED1 is still off)
Replace outdoor unit PWB.
YES
Replace expansion valve.
3 – 10
Normal resistance value
(+)
N
(several M )
Disconnect (CN3) lead
wires of FAN motor.
Disconnect (CN12)
expansion valve.
NO
LED1 is flashing.
Replace outdoor unit PWB.
NO
LED1 is flashing.
YES
Replace FAN motor.
Replace outdoor unit PWB.