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Troubleshooting 
 CAUTIONS
If one of the following conditions occurs, switch o the power supply immediately and contact 
your dealer for further assistance. 
• 
The operation light continues to flash rapidly after the unit has been restarted.
• 
The remote control buttons do not work.
• 
The unit continually trips fuses or circuit breakers.
• 
A foreign object or water enters the air conditioner.
• 
Other abnormal situations.
• 
The indoor unit leaks.
Common Problems
The following symptoms are not a malfunction and in most situations will not require repairs.
Problem Possible Causes
Unit does not 
turn on when 
pressing ON/ 
OFF button 
The unit has a 3-minute protection feature that prevents the unit from 
overloading. The unit cannot be restarted within three minutes of being 
turned o. 
Cooling and Heating Models: If the Operation light and PRE-DEF (Pre-heating/
Defrost) indicators are lit up, the outdoor temperature is too cold and the unit’s 
anti-cold wind is activated in order to defrost the unit.  
In Cooling-only Models: If the “Fan Only” indicator is lit up, the outdoor 
temperature is too cold and the unit’s anti-freeze protection is activated in 
order to defrost the unit. 
The unit changes 
from COOL mode 
to FAN mode  
The unit changes its setting to prevent frost from forming on the unit. Once 
the temperature increases, the unit will start operating again. 
The set temperature has been reached, at which point the unit turns o the 
compressor. The unit will resume operating when the temperature fluctuates 
again. 
The indoor unit 
emits white mist 
In humid regions, a large temperature dierence between the room’s air and 
the conditioned air can cause white mist.  
Both the indoor 
and outdoor units 
emit white mist  
When the unit restarts in HEAT mode after defrosting, white mist may be 
emitted due to moisture generated from the defrosting process. 
The indoor unit 
makes noises 
A squeaking sound is heard when the system is OFF or in COOL mode. The 
noise is also heard when the drain pump (optional) is in operation. 
A squeaking sound may occur after running the unit in HEAT mode due to 
expansion and contraction of the unit’s plastic parts. 
Both the indoor 
unit and outdoor 
unit make noises  
A low hissing sound may occur during operation. This is normal and is caused 
by refrigerant gas flowing through both the indoor and outdoor units. 
A low hissing sound may be heard when the system starts, has just stopped 
running or is defrosting. This noise is normal and is caused by the refrigerant 
gas stopping or changing direction. 
The outdoor unit 
makes noises 
The unit will make dierent sounds based on its current operating mode.
Troubleshooting
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