Choose Product
Identify Problem
03
Find Solutions

LG Air conditioner won't turn off

If your LG air conditioner won’t turn off, the unit is usually trying to make up for a cooling or control problem rather than simply ignoring the setting. The most likely cause is dirty condenser coils, which prevent heat from leaving the refrigerant and can make the compressor run continuously while the air conditioner keeps running to reach the set temperature. Next, check the temperature control thermostat or thermostat. If either one is shorted or not reading correctly, it can keep sending voltage to the fan motor and compressor even when the room is already cool. A dirty or damaged air filter can also restrict airflow and make the LG AC run continuously because the unit cannot cool efficiently. If those parts check out, the thermistor may be sending the wrong room temperature signal to the control board, or the relay board may be supplying constant voltage to the compressor. Enter your LG air conditioner model number on RepairClinic.com to find the exact replacement thermostat, thermistor, air filter, relay board, or other part that fits your unit.

01 - Condenser Coils are Dirty

The condenser coils dissipate the heat as the refrigerant passes through the coils. If the condenser coils are dirty, they won’t be able to dissipate the heat as effectively. As debris builds up on the coils, the air conditioner will become less efficient, causing the air conditioner to work harder to cool down. If the coils are significantly dirty, the air conditioner will not be able to maintain the proper temperature, and the compressor will run continuously in an attempt to cool the room. Check the condenser coils to determine if they are dirty. Refer to owner's manual for cleaning instructions.
Top Solution

02 - LG Air Conditioner Temperature Control Thermostat

The temperature control thermostat provides voltage to the fan motor and compressor. If the thermostat has shorted out, it might send continuous voltage to the compressor and cause the compressor to run all the time. To determine if the thermostat is shorted out, use a multimeter to test it for continuity. If the thermostat has continuity all the time, this indicates that it is shorted out and should be replaced. (Note: Some thermostats may also control a heater and, as a result, will have three terminals. Refer to your air conditioner’s wiring diagram for more information.)
Enter model number to search for the required part specific to your product
Highly Likely

03 - LG Air Conditioner Thermostat

The thermostat monitors the temperature of the air. When the air temperature rises above a set point, the thermostat activates a switch to provide power to the fan and compressor. If the thermostat is defective, it may cause the compressor to run continuously. To determine if the thermostat is defective, set the air conditioner to cooling and then use a multimeter to test the thermostat for continuity. If the thermostat does not have continuity while the air conditioner is set to cooling, replace the thermostat. (Note: Some thermostats may also control a heater and, as a result, will have three terminals. Refer to your air... conditioner’s wiring diagram for more information.)
Highly Likely

04 - Dirty or Damaged Air Filter

A dirty air filter will greatly reduce the cooling capacity of the air conditioner, which may cause the unit to run longer than normal. Most air filters used in stand-alone air conditioners can be cleaned with soap and water. Only filters that are extremely clogged with debris or damaged will need to be replaced. Refer to owner's manual for guidance.
Common

05 - LG Air Conditioner Thermistor

The thermistor is a sensor which detects the room air temperature. It is connected to the control board. If the thermistor is defective it will not have continuity when it should. If this happens the compressor runs all the time.
Common

06 - LG Air Conditioner Relay Board

The relay board provides voltage to many of the air conditioner components, including the fan motor and compressor. If there is a problem with the relay board, it might provide continuous voltage to the compressor. However, this is almost never the case. Before you replace the relay board, make sure you check more commonly defective parts. If you are certain that all of the other components are working properly, replace the relay board.
Common

Frequently Asked Questions

Why won't my LG air conditioner turn off?
Why is my LG AC compressor running constantly?
Can a dirty air filter make an air conditioner keep running?
How do I test an LG air conditioner thermostat or thermistor?
How do I find the right replacement part for an LG air conditioner that keeps running?

Shop by LG Air Conditioner Parts