If a wonky air conditioner has you breaking a sweat on a summer's day, look for error codes. Your LG air conditioner's error codes indicate whether you can solve the problem yourself or if a technician will be required. With many LG air conditioner models, error codes start with P, F, E or CH, depending on the model you own. You can avoid seeing some of these error codes by performing DIY maintenance that should be in your routine.
Video of the Day
When to Call the Pros
Several codes are a blinking "do not pass go" when it comes to tinkering under the hood. These can indicate a wiring fault or a motherboard issue, and attempting repairs yourself could void the warranty, cause a larger issue affecting your home's electrical system or pose a fire hazard.
The E1, E2, CH01 or CH02 error codes are all what LG calls "auto-stop protection" errors, meaning the indoor pipe sensor has a short or open circuit. An HVAC technician will need to solve these for safety's sake.
Another auto-stop protection error is the E3 or CH03 code, which indicates that the unit is out of refrigerant. This simply requires adding refrigerant but is typically a job for an HVAC expert.
Full Drain Pans and Water Tanks
A P2 or FL error code means the drain pan could be full, and the E5 code means the water tank could be full. In humid regions, open doors or windows may make units work harder to reduce moisture, thus causing warnings to display more often.
To drain the pan, refer to your owner's manual to locate the drain port cap and remove it before tilting the unit backward to release accumulated water. No water signals the need for an HVAC tech's expertise. After draining, reset the unit by unplugging it for 20 seconds. Plug it back in, turn it on and hopefully it will work well.
If, however, the error codes return, it's time to call the pros. To prevent this error from recurring often, keep doors and windows closed to create a more stable environment. Using the cool mode more than the dry mode is helpful too.
Solving a CH34 Error Code
The CH34 error code is when the safety relay goes "whoa, now" and shuts things down because overheating may be imminent. The two most common causes for overheating are dirty condenser coils overloading the compressor or sun exposure. Cleaning condenser coils regularly with a handheld vacuum during heavy use can help.
To combat sun exposure, the AC needs shade. LG recommends installing an angled awning over the top to create shade while allowing maximum airflow around the unit. Also, turn the temperature higher when you are going out so it doesn't work as hard rather than turning it off, as starting up is harder on the compressor.
Codes That Mean “All Is Well”
Some codes pop up and might stir maintenance panic, but they're indicators that the machine is doing what it's supposed to do. The E4 code is a perfect example. It's saying that there's ice in the evaporator, and defrost mode started to make it go away. This is routine and nothing to sweat. Otherwise, the numeric F codes — F1, F2 and F3 — are simply showing the fan speed and are saying that the machine is functioning normally.