Mitsubishi Electric PUZ-ZM35VKA Service Manual page 49

10-5. 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. Even controlling by the wireless
remote controller, no beep is heard
and the unit does not start operating.
Operation display is indicated on
wireless remote controller.
5. When operating by the wireless
remote controller, beep sound is
heard, however, unit does not start
operating.
6. Remote controller display works
normally and the unit performs
cooling operation, however, the
capacity cannot be fully obtained.
(The air does not cool well.)
OCH653
Factor
1 12 V DC is not supplied to remote controller.
(Power supply display is not indicated on LCD.)
2 1 2–15 V DC is supplied to remote controller, how-
ever, no display is indicated.
• "PLEASE WAIT" is not displayed.
• "PLEASE WAIT" is displayed.
1 A t longest 2 minutes after the power supply "PLEASE
WAIT" is displayed to start up.
2 C ommunication error between the remote controller
and indoor unit
3 C ommunication error between the indoor and outdoor
unit
4 Outdoor unit protection device connector is open.
1 A fter cancelling to select function from the remote
controller, the remote controller operation switch will
be not accepted for approx. 30 seconds.
1 T he pair number settings of the wireless remote
controller and indoor controller board are mismatched.
1 N o operation for 2 minutes at most after the power
supply ON.
2 Local remote controller operation is prohibited.
• Remote controlling adaptor is connected to CN32 on
the indoor controller board.
• L ocal remote controller operation is prohibited by
centralized controller etc. since it is connected to
MELANS.
3 Phenomena of No.2.
1 Refrigerant shortage
2 Filter clogging
3 Heat exchanger clogging
4 Air duct short cycle
49
Countermeasure
1 C heck LED2 on indoor controller board.
(1) When LED2 is lit.
Check the remote controller wiring for
breaking or contact failure.
(2) When LED2 is blinking.
Check short circuit of remote controller
wiring.
(3) When LED2 is not lit.
Refer to phenomena No.3 below.
2 C heck the following.
• Failure of remote controller if "PLEASE
WAIT" is not displayed
• Refer to phenomena No.2 below if
"PLEASE WAIT" is displayed.
1 Normal operation
2 Self-diagnosis of remote controller
3 " PLEASE WAIT" is displayed for 6 min-
utes at most in 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.
4 C heck LED display on outdoor controller
circuit board. Refer to "10-10. FUNCTION
OF SWITCHES, CONNECTORS AND
JUMPERS".
Check protection device connector (63H)
for contact failure.
Refer to "10-9. TEST POINT DIAGRAM".
1 Normal operation
1 Check the pair number settings.
1 Normal operation
2 Normal operation
3 Check the phenomena No.2.
1 • If refrigerant leaks, discharging
temperature rises and LEV opening
increases. Inspect leakage by checking
the temperature and opening.
• Check pipe connections for gas leakage.
2 Open intake grille and check the filter.
Clean the filter by removing dirt or dust
on it.
3 • If the filter is clogged, indoor pipe
temperature rises and discharging
pressure increases. Check if heat
exchanger is clogged by inspecting
discharging pressure.
• Clean the heat exchanger.
4 Remove the blockage.