Mitsubishi Electric MJ-E14CG-S1-IT Service Manual page 12

A
C
12
B
Does the compressor operate?
YES
Is the heat exchanger
(evaporator) cold?
YES
Are the power consumption
and current normal?
YES
Check the resistance of the
tube temperature sensing thermistor.
Nornal:
Abnormal:Open or short
YES
*Note: Do not replace the compressor easily excpet when the overcurrent(Lock),
D
the abnormal noise or the abnormal vibration is occured.
(includes the oil leak in the compressor)
NO
Is the operating environment
low temperature?
(less than 2°C)
NO
Check if there is no disconnection
or contact failure of the connector
( P5 ) and connector pins of power
control board.
OK
Check the current fuse of
motor protector ( 2A/250V ) .
OK
Check the continuity of the
motor protector.
Nornal:Open
Abnormal:Short
Check it at room temperature
*
when the power is off.
OK
Check the resistance of
the compressor.
Nornal:Terminal C-R 28
Abnormal:Open or short
OK
Is there an overcurrent?
(The surface of the compressor is hot.)
NO
Replace the power control board.
NG
Replace the operation control board.
OK
Check the coolant circuit.
(If the coolant leaks.
NO
If the tube clogs.)
The part of the cooler near
the tube temperature sensor
should be at least 10°C lower
than room temperature when
NO
normal.
The bottom of the heat
exchanger has frost when the
quantity of coolant is little by
coolant leaking.
NO
Replace the tube temperature
sensing thermistor
NG
Replace the power control board.
NG
Replace the operation control board.
OK
YES
Dehumidification may not be
possible in low temperature
environments. (The compressor
does not operate by detecting
abnormal low temperature)
NG
Insert the connector
NG
and connector pins
securely.
NG
NG
Replace the current fuse.
NG
NG
Replace the motor protector.
NG
NG
Replace the compressor.
NG
YES
Replace the compressor.
NG
OK
NG Replace the parts that
coolant is leaking or the
tube is clogged.
OK
OK
OK
OK
OK
OK
OK
OK
OK