Mitsubishi Electric PUZ-SWM60VAA Service Manual page 33

9-3. TROUBLESHOOTING OF PROBLEMS
Phenomena
1. Remote controller display does not
work.
2. "Please Wait" display is remained on
the remote controller.
3. When pressing the remote controller
operation switch, the OPERATION
display is appeared but it will be
turned off soon.
4. Remote controller display works
normally and the unit performs
cooling operation, however, the
capacity cannot be fully obtained.
5. Remote controller display works
normally and the unit performs
heating operation, however, the
capacity cannot be fully obtained.
6. For 3 minutes after temperature
adjuster turns off, the compressor
will not start operating even if
temperature adjuster is turned on.
For 3 minutes after temperature
adjuster turns on, the compressor
will not stop operating even if
temperature adjuster is turned off.
(Compressor stops operating
immediately when turning off by
the remote controller.)
7. The compressor does not work after
breaker switched on.
OCH809A
Factor
12 VDC is not supplied to remote controller.
12–15 VDC is supplied to remote controller,
however, no display is indicated.
• "Please Wait" is not displayed.
• "Please Wait" is displayed.
At longest 2 minutes after the power supply
"Please Wait" is displayed to start up.
Communication error between the remote con-
troller and indoor unit
Communication error between the indoor and
outdoor unit
Outdoor unit protection device connector is
open.
After cancelling to select function from the
remote controller, the remote controller opera-
tion switch will not be accepted for approx. 30
seconds.
Refrigerant shortage
Filter clogging
Linear expansion valve fault
Opening cannot be adjusted well due to linear
expansion valve fault.
Refrigerant shortage
Lack of insulation for refrigerant piping
Filter clogging
Bypass circuit of outdoor unit fault
Normal operation
(For protection of compressor)
Normal operation ( For protection of compressor)
The unit might not run, in order to protect the
compressor, when the following two conduc-
tions holds:
1.The unit was not supplied power for a while,
e.g. at the first use of the unit;
2. Ambient and compressor surface are below
freezing temperature.
It may last up to 12 hours until the unit runs.
33
Countermeasure
Check LED2 on indoor controller board.
(1) When LED2 is lit:
Check the remote controller wiring for break-
ing or contact failure.
(2) When LED2 is blinking:
Check short circuit of remote controller
wiring.
(3) When LED2 is not lit:
Refer to No.3 below.
Check the following.
• Failure of remote controller if "Please Wait" is
not displayed
• Refer to No.2 below if "Please Wait" is dis-
played.
Normal operation
Self-diagnosis of remote controller
"Please Wait" is displayed for 6 minutes at most
in the case of indoor/outdoor unit
communication error. Check LED3 on indoor
controller board.
(1) When LED3 is not blinking.
Check indoor/outdoor connecting wire for
miswiring.
(Converse wiring of S1 and S2, or break of
S3 wiring.)
(2) When LED3 is blinking.
Indoor/outdoor connecting wire is normal.
Check LED display on outdoor controller circuit
board. Refer to "9-9.TEST POINT DIAGRAM".
Check protection device connector (63L and
63H) for contact failure.
Normal operation
If refrigerant leaks, discharge temperature rises
and LEV opening increases.
Inspect leakage by checking the temperature
and opening.
Check pipe connections for gas leakage.
Clean the filter of water piping.
Discharge temperature and indoor heat
exchanger temperature does not rise.
Inspect the failure by checking discharging
pressure.
Replace linear expansion valve.
If refrigerant leaks, discharge temperature rises
and LEV opening increases.
Inspect leakage by checking the temperature
and opening.
Check pipe connections for gas leakage.
Check the insulation.
Clean the filter of water piping.
Check refrigerant system during operation.
Normal operation
Start operating after 12 hours of power-on.