39
Check of defrost heater
M
Replace the inverter P.C. board.
Is there 230V AC between CN722
1
and
3
on the
power P.C. board? Refer to 11-7.2.
Yes
No
No problem of the
power P.C. board.
Is the voltage between CN726
2
(+)-
3
(-)
on the
power P.C. board 0V DC? Refer to 11-7.2.
Yes
No
Replace the power
P.C. board.
NOTE: In case both thermistors are more than the above
temperature, cool them with cold water etc...
In HEAT mode, for more than 5 minutes, let the ambient temperature thermistor continue to read 5
:
or less, and let the
defrost thermistor continue to read -1
:
or less.
3
2
1
230V AC
Check the following points before checking electric continuity.
1) Does the resistance of ambient temperature thermistor have the characteristics? Refer to 11-7.1.
2) Is the resistance of defrost heater normal? Refer to 11-5.
3) Does the heater protector remain conducted (not open)?
4) Are both ambient temperature thermistor and circuit of defrost heater securely connected to connectors?
26H
CN726
CN722
H
2
1
2
1
2
3
Outdoor base gets frozen.
<MUZ-GA25VAH MUZ-GA35VAH>
Check of inverter P.C. board
N
Outdoor fan motor does not operate, or stops immediately after starting up.
Yes
(10-time flash)
Check the LED indication on
the inverter P.C. board.
Does LED indicate 10-time
flash?
No
Replace the inverter P.C. board.
CN931
CN932
Inverter P.C.board
(Solder side)
Outdoor fan motor protection
Check the corresponding section by
LED indication.
Make the outdoor unit operate by
starting EMERGENCY OPERATION .
Check the connection of the connectors.
CN932 : driving output
CN931 : feedback signal
Check the outdoor fan motor.
Refer to11-6.
I
.
OB379 --2qxp 05.1.17 16:38 Page 39
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