What it means
LG Canada's chart describes it as a communication failure from the indoor unit to the outdoor unit. LG lists E0 alongside CH05 and CH53 as communication errors. LG's two US CH05 pages differ on the wait time after switching off: one says 3 minutes, the other 5.
What to check, in order
- Check the outdoor unit's breaker
Look at your consumer unit or breaker panel to see if the breaker for the outdoor unit has tripped. LG notes that some systems have a separate breaker for the indoor unit.
- Switch both off, then on together
If the outdoor breaker has tripped, switch off the indoor unit's breaker as well. Wait 3 to 5 minutes, then switch both back on at the same time.
- Call the installer if it is a new install
LG says a communication code that appears shortly after installation often means a loose connection, so contact the company that fitted it.
When to call an engineer
If the breaker keeps tripping, there is no dedicated breaker for the outdoor unit, or the code comes back after a reset, LG says to have a service technician inspect it. LG lists faulty wiring, a loose connector or a main circuit board problem as possible causes.
Good to know
- On newer LG models where each unit has its own power cord, LG says CH237 means the outdoor unit is getting no power, so check its plug is pushed in firmly. LG's US page pairs CH237 with CH247 and LG Africa pairs it with CH238.
Quick answers
What does the LG CH05 error code mean?
The indoor unit has lost contact with the outdoor unit, so the system has stopped. LG's own CH05 guide puts a tripped circuit breaker for the outdoor unit first on its list. LG Canada's chart describes it as a communication failure from the indoor unit to the outdoor unit. LG lists E0 alongside CH05 and CH53 as communication errors. LG's two US CH05 pages differ on the wait time after switching off: one says 3 minutes, the other 5.
Can I fix LG CH05 myself?
Very easy (about 10 minutes). Start with: check the outdoor unit's breaker; switch both off, then on together; call the installer if it is a new install. If the breaker keeps tripping, there is no dedicated breaker for the outdoor unit, or the code comes back after a reset, LG says to have a service technician inspect it. LG lists faulty wiring, a loose connector or a main circuit board problem as possible causes.
Is LG CH05 worth repairing?
Usually free. Often a tripped breaker or a power glitch, which a reset clears. If it keeps coming back, the wiring or a board needs checking.
Checked against
- LG USA: System air conditioner, a CH05 error occurs
- LG USA: Troubleshooting a CH05 error code
- LG USA: How to troubleshoot error codes CH05, 53, E0, CH32, 33, 36, 38, F4, CH66, 90, 91, 92 and 93
- LG Canada: Single / Multi-Split Air Conditioner Error Codes
- LG Africa: LG Air Conditioner, Guide to Error Codes
Last reviewed October 2026. Manufacturers update their pages, and your manual is the final word. Spotted a mistake? Email contact@appliance-error-codes.com.