Common Problems With LG Air Conditioners

Hunker may earn compensation through affiliate links in this story. Learn more about our affiliate and product review process here.

Were you expecting a refreshing blast of air only to end up with no response from your AC? Troubleshooting common problems with LG air conditioners can help you return those cooling breezes without having a technician visit. Some minor issues with the air conditioner are easy to fix, but others require a professional touch.


LG Air Conditioner Isn't Cooling

A unit that runs but doesn't cool properly could have a few different issues. Verify that it's getting enough power. If it's not plugged into the correct type of power outlet, it might have issues cooling properly. Check your model's manual for specific power requirements.


Video of the Day

High outdoor temperatures can make it difficult for the air conditioner to keep up. Drafts, open windows, or an open fresh air vent on the air conditioner can let hot outside air into the room. This also makes it more difficult for the AC to cool properly. If the unit is too small for the room, it might run nonstop without getting cool enough.

Check the compressor by unplugging the air conditioner for at least 30 seconds. If you turn it back on sooner, the safety switch might kick into effect and stop the unit from running for three minutes. After plugging it back in, choose the cool setting on the lowest temperature. The compressor should start running in about 30 seconds, and you should be able to hear the startup and the hum of the compressor running. If you don't hear it, the unit likely needs a professional repair.


AC Won't Turn On

Check the power source before assuming your LG air conditioner is broken. Verify that the unit is plugged in completely. Some newer models have a GFCI on the electrical cord, so hitting the "reset" button might solve the power issue. Test a lamp or another small appliance in the electrical outlet to see if it's an issue with the outlet or the air conditioner.


If the other appliance doesn't work, check the circuit breaker for the air conditioner to verify that it's turned on. Flip the breaker back to the "on" position if it was tripped. LG air conditioners need a dedicated circuit to handle the power draw safely. If you use the circuit for other items, it's more likely to become overloaded.

AC Doesn't Run

Sometimes, you can power up your LG air conditioner, but it won't run. Insufficient power is often the cause, which can happen if you have the air conditioner on the same circuit as other items. There's enough power running to the unit to turn it on and to operate the display but not enough for it to run.



Another possibility is that the room temperature is the same as the temperature you have set on the air conditioner. Once the room reaches the desired temperature, your LG air conditioner stops running. If the temperature rises, it starts running again. Lower the temperature setting to see if the LG AC starts running. If not, call a professional to diagnose and repair the problem.

AC Turns Off and On

If it seems like your AC turns on and off every few minutes, it could be the wrong size for the room. Getting the correct air conditioner size helps the unit cycle properly. If it's oversized for the room, the air conditioner often short cycles, running for just a short time before turning off. While it might keep the room cool, it usually doesn't run long enough to dehumidify the room, so it can feel damp.


AC Error Codes

Some LG models give you a clue about the issue with error codes. Specific codes can vary by model, so check the manual for guidance. Some examples of codes include:

  • P2 or FL:​ Full drain pan.

  • CH34:​ Shut down from the safety relay to avoid overheating due to abnormal pressure.

  • E1 or CH02:​ Short or open circuit in the indoor pipe sensor; requires repair.

  • E3 or CH03:​ No refrigerant detected; requires professional repair.

  • E4:​ Indicates defrost mode (not an actual error) with AC turning on after it defrosts.

  • E5:​ Full water collection tank.

  • F1, F2, F3:​ Not an error code but an indicator of fan speed.



Report an Issue

screenshot of the current page

Screenshot loading...