LG CH 05 error code

What it means

CH 05 means the indoor unit and outdoor unit are not exchanging the expected control signal. It often shows up right after installation or relocation if the connection is wrong, but LG also notes that normal-use faults can be temporary after unstable power.

Urgency

Likely causes

1. Communication issue between the indoor and outdoor units
2. Installation or relocation connection issue
3. Temporary fault from unstable power or other electrical factors
4. Indoor or outdoor communication circuit needing service

Homeowner fix

Turn the system off, then power cycle once at the breaker or disconnect if you can do that safely. Do not open wiring covers or touch the communication cable.

When to call a pro

Call a licensed HVAC technician if CH 05 returns after one reset or appeared right after installation. Tell them LG identifies CH 05 as indoor/outdoor communication.

Repair vs replace

Communication faults are usually repairable wiring, setup, or board issues. Compare repair with replacement only if an older out-of-warranty system needs multiple boards or major electrical work.

• LG Mega R-32 9,000 BTU (115V)

  Mega R-32

• LG Mega R-32 9,000 BTU (230V)

  Mega R-32

• LG Mega R-32 12,000 BTU (115V)

  Mega R-32

• LG Mega R-32 12,000 BTU (230V)

  Mega R-32

For your technician

Technician note: verify indoor/outdoor power, communication wiring, terminal order, cable condition, and communication boards before clearing the code. Page context: LG maps this display to the Mega R-32 line; source: LG official support pages: [LG Air Conditioner] Guide to Error Codes; [LG Air Conditioner] How to Check Air Conditioner Error Codes; LG status-display help articles; LG Korea [LG Air Conditioner] Air conditioner error inquiry cross-check; display convention: match the letter C, letter H, and five marker exactly before comparing neighboring codes.

Which systems show it

Mega R-32

Related troubleshooting

Use the symptom guide alongside the exact display code if the unit is flashing, cycling, or showing comfort symptoms.

Related codes

Source

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