LG aircon CH04 / FL error code & blinking light
Use this LG CH04 / FL guide to capture the fault correctly and see what should be checked before parts are quoted. Match the model first; same-looking signals can point to different rows.
What does LG CH04 / FL mean?
LG CH04 / FL is listed as optional float switch or drain-pump error, indoor unit: Indoor drain overflow error, and drainage issue or condensate tank full in Wall-Mounted Split, VRF, Cassette rows such as HSV4 / HSV5 single-zone wall-mounted systems, LG Multi V 5 commercial VRF. 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.
Choose the matching source row
The same visible code has more than one source-backed meaning. Match the model family, system type, or reporting unit before approving parts.
| Code | What it means | What to check first |
|---|---|---|
| HSV4 / HSV5 single-zone wall-mounted systems | Optional float switch or drain-pump error. | Match this row to the installed model or reporting unit, then use the source-specific checks below. |
| LG Multi V 5 commercial VRF | indoor unit: Indoor drain overflow error | Match this row to the installed model or reporting unit, then use the source-specific checks below. |
| Ceiling Cassette | Drainage issue or condensate tank full. | Match this row to the installed model or reporting unit, then use the source-specific checks below. |
What to do now
Use these steps before running the unit again or approving drain or pump work.
Treat it as a fault signal
Stop using the unit if CH04 / FL returns, water leaks, or the drain pan keeps filling.
No manufacturer reset steps listed for CH04 / FL
Capture the complete CH04 / FL pattern and model stickers first. The selected source row lists no customer reset procedure; do not treat a generic power-cycle as manufacturer guidance.
Send these to us
CH04 / FL error code and blinking light, a clear display photo and blinking-light video if the unit shows one, LG model stickers, affected rooms, operating state when the code appeared, and where water appears
Source-specific guidance
These diagnostic-reference notes help match the code to the exact model. Electrical, refrigerant, wiring, resistance, and component checks are technician work, not DIY steps.
| Source detail | What it says |
|---|---|
| Diagnostic note | Optional float switch or drain-pump error. If a condensate pump or float switch is fitted, check the drain pan, pump operation, float wiring, and float connector before indoor PCB diagnosis. |
| Diagnostic note | Record 04 and confirm that the indoor unit reported it. Stop the affected indoor unit if water is present; check only for an obvious drain obstruction, then arrange drain-pump and float-switch diagnosis. |
| Diagnostic note | Drainage issue or condensate tank full. For ceiling units, check whether condensate is draining. For window or portable units, drain the condensate tank and request service if CH04 or FL returns. |
| Singapore / model note | Official LG HVAC HSV4 / HSV5 wall-mounted self-diagnosis table. Keep this separate from the CH04 / FL drainage row for window, portable, and ceiling units. |
| Singapore / model note | LG Singapore lists Multi V 5, but the installed unit nameplate and matching service manual control. Do not apply this row to Multi V i or another LG family. |
| Singapore / model note | Official LG help-library guide; CH04 can point to different faults by product type, so keep this drainage row separate from the technical PDF heat-sink/float-switch row. |
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 taking any system action on CH04 / FL, take a clear display photo and blinking-light video if the unit shows one. | Confirm whether CH04 / FL is drain overflow, float switch, pump, or water-level protection. |
| Capture the LG indoor and outdoor model stickers so the correct family row is used. | Clear and flow-test the drain route, then check pan level and float operation. |
| The selected source row lists no customer reset procedure. Note whether one room, several rooms, or the whole system is affected. | Test pump power, pump discharge, and slope on cassette or concealed units. |
Drain clearing or pump decision
LG CH04 / FL normally stays in repair scope: clear the drain, test the float or pump, and check slope before discussing replacement.
A blocked drain is usually a service-level repair if flow returns after clearing.
Pump or float-switch work needs part testing before replacement is approved.
Concealed drainage problems become labour-heavy because access decides the repair path.
LG CH04 / FL questions
What does the LG CH04 / FL error mean?
Can I fix a LG CH04 / FL error myself?
Is it safe to keep running the aircon with a CH04 / FL error?
What causes a LG CH04 / FL error?
Will a LG CH04 / FL error need a repair or a full replacement?
What should I send a technician about a LG CH04 / FL error?
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Use these if the quote mentions the parts, checks, or repair path this code points to.