LG aircon CH04 / FL error code & blinking light
Use this LG CH04 / FL guide to decide when to stop resetting, what to capture, and what to check 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 and drainage issue or condensate tank full in Wall-Mounted Split, Ceiling Cassette, Window Unit rows such as HSV4 / HSV5 single-zone wall-mounted systems. 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.
Blocked drain pipe, trap, or concealed drain route.
Float switch or drain-level protection triggered by water in the pan.
Drain pump, drain slope, or pan-level issue after clearing is attempted.
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.
Reset CH04 / FL once
Capture the CH04 / FL pattern, then stop the unit if water is leaking or the drain pan looks full. Power-cycle once only if the area is dry.
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, reset result, and where water appears
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 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. |
| Note whether one room, several rooms, or the whole system is affected, plus whether it returns after one reset. | Test pump power, pump discharge, and slope on cassette or concealed units. |
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 CH04 / FL. | The affected room, indoor board path, wiring route, or local component should be checked first. |
| Several rooms or the outdoor unit show the same CH04 / FL fault. | The shared outdoor side, power path, communication trunk, or refrigerant circuit needs priority checking. |
| Water appears at the indoor unit or ceiling area. | Drain flow, float switch, pump, and pan level should be checked before running again. |
| 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, Ceiling Cassette, Window Unit rows such as HSV4 / HSV5 single-zone wall-mounted systems. | The loaded row is source-backed by official diagnostic material. Use the matching source row before quoting parts. |
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.
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 CH04 / FL, jump to one of these or browse the full LG list.
Ready to get started?
Tell us what’s going on. Symptoms, setup, photos, anything we should know. We’ll assess and come back with the right next step.