LG’s room air conditioner lineup – window, portable and in-wall units – is one of the deepest catalogues it sells in the US, and nearly all of it reports faults through the same CH-prefixed scheme, distinct from the F-codes on LG’s ranges or the letter codes on its washers and dryers. A no-cooling complaint on any of them follows a fairly short diagnostic path: airflow first, then the electrical controls, then the sealed system, in that order, because most calls resolve well before the last step.
We check the filter and the airflow path, the thermostat or sensor and the control board, and the capacitor and compressor relay before considering anything inside the refrigerant circuit. Installation matters here too – a window unit tilted the wrong way drains water into the room instead of outside, and a unit sized wrong for the room will short-cycle or never bring the humidity down properly, regardless of how well every part inside it is working.
Where the fault does turn out to be in the sealed system, that work is carried out only by a technician equipped and licensed to handle refrigerant, and because the repair cost on an inexpensive room unit can approach the price of a new one, we give you that comparison plainly before any work begins.
Common Air Conditioners Problems
Unit running but blowing air that is not cold
Short-cycling on and off every few minutes
Ice forming on the indoor coil or front grille
Water dripping inside the room instead of draining to the outside
CH-code shown on the display along with the unit shutting down
FL shown with the unit not cooling, especially on a humid day
Air Conditioners Error Codes
Recognize a code on your display? Look it up before you unplug anything or attempt a repair.
Display Turned Off / Not Turned On (Brightness Setting)
LG Air Conditioner Display Off Indicator (Not a Fault)
LED Blinking After Power Off (Auto Drying)
LG Air Conditioner LED Blinking After Power Off (Not a Fault)
LED Too Bright
LG Air Conditioner LED Too Bright (Not a Fault)
Lamp Does Not Light (Filter Alarm Timing)
LG Air Conditioner Lamp Not Lighting After Power Off (Not a Fault)
Lo
LG Air Conditioner Lo Indicator (Not a Fault)
"7" or "L" (Comfort Air Wind Angle)
LG Air Conditioner "7" or "L" Indicator (Not a Fault)
Clean Filter
LG Air Conditioner Clean Filter Message
CH01, CH02, CH06, CH12, CH41, CH42, CH43, CH44, CH45, CH46, CH47, CH48, E1, E2, E3, E7, E8
LG Air Conditioner Sensor Fault Codes
"Outdoor Unit" Message
LG Air Conditioner "Outdoor Unit" Display (Not a Fault)
CH21, CH23, CH26, CH29, E9
LG Air Conditioner Compressor / Outdoor Unit Fault Codes
F1, F2, F3 (Room Air Conditioner Fan Speed - Not a Fault)
LG Air Conditioner F1 / F2 / F3 Fan Speed Indicator
CH03
LG Air Conditioner CH03 Error Code
Popular LG Air Conditioners Models
LG LW1424RD
Model # LW1424RD
LG LW1812ERS
Model # LW1812ERS
LG LW1821ERSM
Model # LW1821ERSM
LG LW2413HR
Model # LW2413HR
LG LW2423HR
Model # LW2423HR
LG LW5014
Model # LW5014
Why Trust Us With Your LG Air Conditioners
- Trained on LG air conditioners control systems and diagnostics.
- Genuine OEM parts stocked for the most common failures.
- Upfront flat-rate pricing, approved by you before we start.
- 30-day workmanship warranty on every repair. Parts may carry the manufacturer's warranty where applicable.

