Service manual

96
CC
Check of indoor electronic control P.C. board
Check the both “parts side” and “pattern
side” of indoor electronic control P.C.
board visually.
Replace the fuse.
Is fuse (F11) blown?
Be sure to check both fuse
and varistor in any case.
Replace the fan motor.
Replace the indoor
electronic control
P.C. board.
Is winding
resistance of
fan motor 0 "?
Is winding
resistance of
vane motor 0 "?
No
Yes
Replace the vane
motor.
No
Yes
Yes
Is varistor (NR11) burnt?
Replace the varistor.
Yes
Turn OFF the power supply.
Remove indoor fan motor connector CN211 and
vane motor connector CN151 from the indoor electronic
control P.C. board and turn ON the power supply.
No
No
Does the unit operate with the remote controller?
Does the OPERATION INDICATOR lamp light up
by pressing the EMERGENCY OPERATION switch?
Yes
No
Be sure to check both resistances.
Turn OFF the
power supply.
Turn OFF the
power supply.
The unit doesn’t operate with the remote controller.
Also, the OPERATION INDICATOR lamp doesn’t light up by pressing the EMERGENCY OPERATION switch.
DD
Check of outdoor unit
Compressor and/or outdoor fan motor doesn’t operate.
Yes
Compressor
doesn't operate.
Yes
Yes
Is there 230V AC between 3 on the
compressor contactor (52C) and N
on the outdoor terminal block (TB1)?
Operate the unit in COOL or HEAT mode by pressing the EMERGENCY OPERATION switch.
3-minute time delay works.
Test run operation operates for 30 minutes.
Outdoor fan motor
doesn't operate.
No
Rectify the indoor and
outdoor connecting wire.
Rectify the connecting wire.
Check the compressor and compressor
capacitor, and rectify the connecting wire.
Start
Yes
Is there 230V AC between 4 on the
compressor contactor (52C) and
TAB20 on the deicer P.C. board?
Is there 230V AC between L–N
on the outdoor terminal block (TB1)?
Replace the
deicer P.C. board.
Replace the
deicer P.C.
board.
No
No
Yes
Yes
No
Check the outdoor fan motor
and rectify the connecting
wire.
Is there 230V AC between 4 on the
compressor contactor (52C) and
TAB 20 on the deicer P.C. board?
Replace the
deicer P.C. board.
No
Yes
Rectify the indoor and
outdoor connecting wire.
Rectify the connecting wire.
Is there 230V AC between L–N on
the outdoor terminal block (TB1)?
No
No
Is the switch SW2-2 on the
indoor electronic control
P.C. board set to MUH type?
No
Change the switch SW-2-2
on the indoor electronic control
P.C. board to MUH type.
Yes
+
–
Is there 5V DC between J205 –J101 on
the deicer P.C. board?
+
–
Is there 5V DC between J205 –J101 on
the deicer P.C. board?
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