Mitsubishi Electric MUFZ-KJ25VEHZ, Руководство по обслуживанию

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N 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?
Is there 230 VAC between CN722 and
(
MUFZ-KJ25/35 )/CN601 and ( MUFZ-KJ50 )
on the inverter P.C. board? Refer to 11-6.1.
Not the problem of the inverter P.C. board.
Replace the inverter P.C. board.
No
Yes
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.
NOTE: In case both thermistors are more than the above temperature, cool them with cold
water etc...
Has the operation stopped
during pump down?
Was the operation started with
the stop valve closed, and was
it opened during operation?
No
Yes
O Check of outdoor refrigerant circuit
The operation has stopped to pre-
vent the diesel explosion caused by
air trapped in the refrigerant circuit.
Close the stop valve, and disconnect
the power plug or turn the breaker
OFF.
The unit occasionally stops when the
stop valve is opened or closed during
operation. Open the stop valve and
start the cooling operation again.
Yes
No
The refrigerant gas amount may be
60% or less than the normal amount.
Identify where the gas is leaking from,
and fi x the leak.
CAUTION : Do not start the opera-
tion again to prevent
hazards.
OBH668E