LG Aircon CH25 Error Code & Blinking Light
LG CH25 points to aC low or high voltage and system voltage too low or too high. The loaded rows include more than one source meaning: aC low or high voltage and system voltage too low or too high. The source is official, but the exact model or series still decides the applicable row.
What Does LG CH25 Mean?
LG CH25 is listed as aC low or high voltage and system voltage too low or too high in Wall-Mounted Split rows such as HSV4 / HSV5 single-zone wall-mounted systems, LS091HSV / LS121HSV wall-mounted single-zone. The loaded row is source-backed by official diagnostic material. Do not collapse this code across model families; use the model, series, or system type to choose the right row. Confirm the exact model, series, or signal row before accepting a parts quote.
Voltage, current, fuse, module, or power-supply protection has been triggered.
Loose connector, damaged harness, or outdoor electrical component fault.
PCB or inverter-module issue after power and load checks are confirmed.
What To Do Now
Use these steps before another reset or parts quote.
Stop using the unit if CH25 returns
Stop repeated restarts if CH25 returns, trips power, smells burnt, or the outdoor unit runs unusually hot.
Reset CH25 once
Capture the CH25 pattern, then reset once only if there is no burning smell, repeated trip, or hot outdoor unit.
Send these to us
CH25 error code and blinking light, a clear display photo and blinking-light video if the unit shows one, LG model stickers, affected rooms, reset result, and trip timing and outdoor-unit behaviour
Send Us What You're Seeing
Share CH25, your LG model, and what happened before it appeared. We'll read it and respond with the right next step before any work is approved.
What To Check Before Repair
Use this split to separate safe evidence capture from the tests a technician should prove before quoting parts.
| You Can Check | Technician Should Confirm |
|---|---|
| Before resetting CH25, take a clear display photo and blinking-light video if the unit shows one. | Confirm whether CH25 is voltage, current, module, fuse, or protection related. |
| Capture the LG indoor and outdoor model stickers so the correct family row is used. | Check incoming voltage, connectors, inverter module, and current draw under load. |
| Note whether one room, several rooms, or the whole system is affected, plus whether it returns after one reset. | Confirm downstream loads before replacing electrical boards or modules. |
What Changes The Next Step
These clues decide whether the first check is room-side, shared outdoor-side, refrigerant-side, source-table, or model-family confirmation.
| What You See | What It Points To |
|---|---|
| Only one indoor unit shows CH25. | The affected room, indoor board path, wiring route, or local component should be checked first. |
| Several rooms or the outdoor unit show the same CH25 fault. | The shared outdoor side, power path, communication trunk, or refrigerant circuit needs priority checking. |
| The fault returns immediately after one reset. | Start with the source-row diagnostic branch before approving parts. |
| The same code appears with different meanings in the source rows. | Model family, source table, and system type decide which meaning applies before parts are quoted. |
| The model belongs to Wall-Mounted Split rows such as HSV4 / HSV5 single-zone wall-mounted systems, LS091HSV / LS121HSV wall-mounted single-zone. | The loaded row is source-backed by official diagnostic material. Use the matching source row before quoting parts. |
Electrical Module Or Wiring Decision
LG CH25 needs voltage, current, module, and load checks before parts are quoted. The repair path depends on whether the fault is supply-side, wiring-side, or board-side.
Supply voltage and load checks separate building-side issues from unit-side faults.
Module or inverter faults need measured current and voltage evidence.
Repeated electrical trips should not be cleared repeatedly without diagnosis.
Read Next
Use these if the quote mentions the parts, checks, or repair path this code points to.
Other LG Error Codes
If the code you're seeing isn't CH25, jump to one of these or browse the full LG list.
Ready to Get Started?
Send the CH25 error code and blinking light, a clear display photo and blinking-light video if the unit shows one, and LG model sticker. Send the model sticker so the matching official row can be checked quickly. We can help separate supply, module, load, and board checks.