LG Mini Split H25 Error Code

What H25 means

H25 (CH25) means the outdoor unit supply voltage is outside the rated range - the system stops to protect the inverter and compressor electronics. SplitAtlas (anchored to LG's support table) lists supply voltage above and below rating as the causes; MyPros+ independently describes LG CH25 as a power-supply fault with input voltage outside the safe operating range; Snowflake Aircon groups CH25 with electrical faults needing service if one reset does not clear it.

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.