LG Mini Split H05 Error Code

Updated 2026-08-30 · review status: manual-verified · reviewed by MiniSplitDecoder Editorial Team Last verified: 2026-08-30

Check your model first

  • Models that display codes without the CH prefix

Match the model on your equipment label to the linked manufacturer documentation. The same code can mean different things across model families.

Quick answer

H05 on LG units (displayed as CH05) is a communication error between the indoor and outdoor units. Check the outdoor breaker and power both breakers off for 5 minutes, then back on together - if the code persists, wiring or board service is required.

Severity: high · DIY difficulty: easy

Safety

Stop at the breaker power-cycle and any plug-accessible checks (filters, remote settings, visible wiring). The outdoor unit's capacitor holds a lethal charge and the refrigerant circuit is both pressurized and (on R-32 units) flammable — opening panels or servicing the sealed system is licensed-technician work (EPA 608).

What H05 means

H05/CH05 means the indoor and outdoor units are not exchanging signals normally. LG's official guidance is to check whether the outdoor-unit breaker tripped, switch both indoor and outdoor breakers off for 5 minutes, restore them together, and call for service if the code persists.

Code meaning varies by series

  • Models that display codes without the CH prefix: Shown as H05 or 05 - same indoor/outdoor communication error

First checks before service

This page currently documents the safe reset triage. If the code returns, use the linked source manual or a qualified technician for code-specific diagnosis.

  1. 1. One-time fault event (power disturbance or transient sensor reading) common DIY

    Check: Power-cycle at the breaker/disconnect (or unplug for CPAP), restore, and run the system while watching for the code.

    Fix: If the code does not return after a full run cycle, the fault was transient — monitor, no repair needed.

  2. 2. Fault persists after a clean reset occasional pro only

    Check: If the code returns immediately or every session, note the conditions (startup, heating, after rain).

    Fix: A persisting code points at the component the manual assigns to this code — that repair is technician territory.

Related codes

Cross-references for the same fault family, by brand:

LG E0 · LG H53 · LG H32 · LG H33

Commonly searched as: "lg h05" · "lg error code h05" · "lg air conditioner h05"

Sources

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