12 TROUBLESHOOTING
Phenomenon
Cause and action
Operation Stopped
All indication lamps on the wired controller
are turned OFF.
The micro-computer is activated to protect the device from
electromagnetic waves. Restart the operation.
After Power Failure
Restart the operation. If the instantaneous power failure is within two
seconds, the operation restarts automatically.
White steam from indoor unit
During the heating operation.
It may occur during the defrosting operation in the heating operation.
White smoke from indoor unit At Beginning of Heating Operation Season
Dust attached to the heat exchanger has been dried.
Mist from indoor unit
The indoor unit is used in a restaurant or a
kitchen.
Oil is attached to the fins and the heat exchange efficiency may be
decreased.
During the dry operation
It may occur when the air outlet temperature becomes lower.
Raise the set temperature and the air flow volume.
The cooling operation is performed in high
humidity environment.
Odor from indoor unit
The air flow from the indoor unit has odor.
It may occur because the cigarette smoke and room odor are stuck
inside the indoor unit.
Ventilate well by the fan mode and clean the air filter, the flat panel,
the air outlet and the air inlet grille. It may be effective for odor
eliminating.
Sound from indoor unit
Sound is heard when starting or stopping
the operation.
It is generated because the resin parts are stretched by the
temperature change and rubbed with other parts.
Sound which water flows or is boiled is
heard during the operation.
It is generated because the refrigerant flows or the drain-up
mechanism drains water. Especially, sound may be heard when
starting the operation or stopping the compressor (for approx. 3
minutes).
Growling sound may be heard temporarily
right after the air flow volume is changed.
It is generated because the fan motor makes temporary sound by
change of fan speed.
Dew on panel
Dew condensation occurs on the panel or
the cabinet or dew drops.
It may occur if the operation is performed in high humidity place
(relative humidity is approx. 80%.) for a long time.
Temperature Irregularity
The air flow volume and temperature of
each air outlet are irregular.
This might occur for structural reasons, such as the size of air outlet
and the location of heat exchanger.
Turned ON “HOT-ST” on LCD
The indications may be turned ON or flash according to the operation
mode or condition.
Flashing operation mode on LCD
Trouble
Checking point
Action
Not operated
Check that the main power source is turned
ON.
Turn ON the main power source for air conditioner.
Check that the fuse does not blow out or
the circuit breaker of main power source is
not tripped.
Replace the fuse or reset the circuit breaker.
If the trouble recurs, contact your contractor or distributor.
Operated
however,
stopped soon
Cooling
Check whether the air inlet and outlet of the
outdoor unit are not covered by a paper, a
vinyl or other object.
Remove objects covering the air inlet and outlet.
Heating
Check whether there are any obstacles for
the air flow near the air inlet and outlet of
the outdoor unit.
Remove the obstacles which prevent the air flow.
Check whether the outlet air is short-
circuited to the air inlet.
Not cooling or heating well
Check that the operation mode is
appropriate.
If the fan mode is selected, switch the operation mode to cooling
(heating).
Check that the set temperature is
appropriate.
If not, change the set temperature by pressing “▲” or “▼” by the
remote control switch.
Check that the air flow direction is
appropriate.
If not, change the air flow direction.
In the case that the footing is not heated well during the heating
operation, change the louver downward.
Check that the air filter is not clogged.
Clean the air filter.
Check that a window and a door are not
opened.
Close the window and the door.
Check that there are no obstacles for the
air inlet and the air outlet of the outdoor unit
and the indoor unit.
Remove the obstacles.
TROUBLESHOOTING
PMML0498 rev.1 - 11/2018 - P5417093
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