Mitsumi electronic AF1200CFM Air Conditioner User Manual


 
6
4. Troubleshooting
Before you ask for repair service, check the following points:
Operation
It does not run.
Air flows out but it does
not cool enough or heat
enough.
Cool air or warm air
does not come out.
It runs briefly, but soon
stops.
The sound of the ex-
haust and rotation of
the motor can still be
heard after operation
stops.
The sound of the ex-
haust and the rotation
of the motor can be
heard intermittently af-
ter stop of running.
Warm air comes out in-
termittently when the
thermostat is OFF or
during fan operation.
Troubleshooting
Press the [ON/OFF] button after power restoration.
Turn the power supply ON.
Replace the fuse.
Install the ground breaker.
After checking the set temperature and inlet temperature
on the liquid crystal display, refer to Room temperature ad-
justment section.
Clean up the filter.
(Refer to Maintenance section.)
Remove.
Close.
Wait for a while.
(To protect the compressor, a 3-minute protection circuit is
built into the indoor unit. Therefore, there are occasions some-
times when the compressor does not start operating imme-
diately. There are cases when it does not run for as long as 3
minutes.)
Wait for a while.
(Heating operation starts after ending defrost ends.)
Rerun after removal.
Rerun after cleaning the filter. (Refer to [Caring for the ma-
chine].)
Wait for 3 minutes.
It soon stops. (If the noise occurs more than 2-3 times in an
hour, call a contractor for service.)
It soon stops. (If the room temperature rises uncomfortably
high in a small room, stop operation.)
Cause
Power failure
The power supply is turned OFF.
The fuse in the power supply is missing.
The ground breaker is missing.
Improper temperature adjustment.
The filter is filled with dust and dirt.
There are some obstacles at the air inlet and outlet of
the indoor and outdoor units.
Windows and doors are open.
The protect on circuit is in operation for 3 minutes.
Indoor unit operation was restarted during the heating
and defrosting operation.
There are some obstacles at the air inlet and outlet of
the indoor and outdoor units.
The filter is filled with dust and dirt.
If the other indoor units are in cooling operation, the
machine stops after operating a drain-lift mechanism
for 3 minutes when air-cooling operation is stopped.
If the other indoor units are in cooling operation, drained
water is brought in. If the drain water is collected, the
drain-lift mechanism initiates.
If the other indoor units are engaged in heating opera-
tion, the control valves are opened and closed from
time to time to maintain system stability.
Remote Controller
'display is not lit up.
No display appears even
when the [ON/OFF] but-
ton is pressed.
The liquid crystal display
shows that it is in the
state of operation.
The liquid crystal display
shows that it is in opera-
tion.
The “check” and check
code flashes on the liquid
crystal display.
All lights are out except
the powered display of
'”.
All lights are out except
the powered display of
'”.
The liquid crystal display
shows that it is in the
state of operation.
If operation stops due to a power failure, the [protection circuit at power failure] operates and disables unit operation even after power is restored. In this case, press the
[ON/OFF] button again and start operation.
If malfunctions persist after the above, turn the power supply OFF and contact the dealer or contractor with information about the product name, the nature of the malfunction,
etc. If the display of “[check]” and (4 digit) check code flashes, tell the dealer or contractor contents of the display (check code). Never repair yourself.
The following symptoms are not air conditioner failures:
The air blown out from the air conditioner can sometimes give off odors. This is due to cigarette smoke contained in the room air, the cosmetics smell, walls, furniture, etc.,
that is absorbed in the air conditioner.
•A hissing noise can be heard immediately after the air conditioner is started or stopped. This is the normal sound of the refrigeration flowing inside the air conditioner.
The air conditioner sometimes snaps or clicks at the beginning or end of cooling/heating operation. This is the normal sound of friction on the front panel and other
sections due to expansion and contraction caused by temperature change.
WT05632X01_en.p65 09/9/17, 15:536