Mitsubishi MJ-E16V-S1 Service Manual page 23

Step 3
Does the compressor operate?
(NO if stalled)
*The compressor does not operate for
3 minutes after turning the power ON
or OFF. (See page 10)
Step 4
Is the heat exchanger (evaporator) cold?
* Check by operating for 30 minutes.
Step 5
Are the power consumption
and current normal?
Step 6
Is the filter blocked?
Step 7
Is the operating environment low
humidity or low temperature?
Is dehumidification taking place?
(Water drops are being collected)
No problem
* If the customer complains that the unit won't dehumidify, make the following checks before starting to repair the coolant
circuit:
1 Clogged filter, or dust: ➞ Action: Clean.
2 Low-temperature, low-humidity operating environment:
➞ Action: See the explanation of the graph on page 11, or move the unit to a kitchen or bathroom and request
verification of its performance.
3 Request checking whether the unit is in an automatically-stopping operation mode such as "EASY DEHUMIDIFYING",
etc.
➞ Action: Verify to dehumidify in "LOW" operation mode. (See pages 6 – 7.)
A
NO
YES
YES
YES
NO
NO
YES
*If error indicators are lit, see Error Indications
and Corrective Actions on page 24.
Is there an overcurrent?
(Surface is hot)
NO
Check connectors
Is the compressor relay
operating properly?
Check resistor values for
temperature sensor (See page 24)
Is the continuity of the
motor protector no good?
(Normal: CLOSE;
Malfunction: OPEN)
*Check when there is no
current and the unit is at
room temperature.
Are the resistor values of
the compressor no good?
(See page 24)
Replace board
NO
Check the coolant circuit.
(Leaks or blockages)
*The part of the cooler near the tube
temperature sensor should be at least 10˚C
lower than room temperature when normal.
NO
YES
Clean filter
YES
Dehumidification may not be possible
in low humidity and low temperature
environments. (See page 10)
NO
Recheck Steps 3 to 5
Replace compressor
Check board
(open/bridge)
Replace sensor or
repair open/bridge
Replace motor protector
Replace compressor
23