Mitsubishi Electric MUZ-FH25VEHZ Service Manual page 44

O Check of defrost heater
Check the following points before checking electric continuity.
1. Does the resistance of ambient temperature thermistor have the characteristics? Refer to 11-6.1.
2. Is the resistance of defrost heater normal? Refer to 11-4.
3. Does the heater protector remain conducted (not open)?
4. Are both ambient temperature thermistor and circuit of defrost heater securely connected to connectors?
In HEAT mode, for more than 5 minutes, let the ambient temperature thermistor continue to read 0°C or
below, and let the defrost thermistor continue to read -1°C or below.
Is there 230 VAC between CN722
(MUZ-FH25/35)/CN601
the inverter P.C. board? Refer to 11-6.1.
Replace the inverter P.C. board.
OBH625A
NOTE: In case both thermistors are more than the above temperature, cool them with cold
water etc...
and
and (MUZ-FH50) on
No
Yes
Not the problem of the inverter P.C. board.
44