The AC in Your Flat
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A damp streak on a painted wall below the corner of a split AC, with a bucket on the floor beneath
AI-generated picture. Water on the wall is condensation that lost its way out.

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Water running down the bedroom wall

Split AC water leakage indoors most often comes from a clogged drain pipe or a filter dirty enough to let ice form on the coil, so clean the filter and call a technician if it still drips.

From The AC in Your Flat. Updated 4 November 2026.

Your AC pulls water out of the room's air all day. That water should run from a tray behind the coil, along a thin pipe, and out of the flat. LG's service film names the usual failures: the drain pipe clogs, the water builds up, and the tray overflows.

Why does the indoor unit overflow?

The second cause starts with the filter. Dirt on the filter cuts the air moving over the coil, the coil falls to freezing, and ice forms in place of moisture. When that ice melts, more water reaches the tray than it can hold. LG also says to keep doors and windows around the AC closed, since humid air coming in adds to the load.

A thin grey drain pipe ending over a floor drain on a utility balcony
AI-generated picture. The other end of the problem. In a society, this pipe should reach a proper drain, not a neighbour's ledge.

What can you do before the technician comes?

Turn off the AC. If water has reached the socket, wiring or the stabiliser, turn off its MCB, keep it off and call an electrician or technician. Put a bucket under the drip and move the bed clear. Move anything electrical only if it's dry and already unplugged. If water has stayed clear of the electrics, clean the filter with the power off, as in the filter story. If the wall stays dry after a few hours of running, you may have found it.

If it drips again, call a technician to clear the drain. Clogged drain lines are among the faults regular servicing is meant to catch. Do not poke wire into the pipe or take the cover off the unit.

From LG's service channel, 80 seconds, English captions. It explains the causes and shows no repair for you to copy. Channel: LG DIY Service.

Why is water dripping from the outdoor unit too?

That one is usually fine. LG India's outdoor unit film compares it to dew on a cold bottle from the fridge, and calls it a sign of normal operation. If it bothers you, LG suggests a bucket. Only do that where the unit stands on a floor you can walk on. For a unit on a ledge, ask a technician about the pipe instead, and read who should reach it first.

Older flats in Pune behind a thick screen of green trees in humid light
Humid air means more water in the tray. Older pipes get more of a test in the wet months.
Old balconied flats in Mazagaon behind a tree
Older blocks often have drain pipes added afterwards. Follow yours with your eye from the balcony; never lean out to do it.

What to do

Yours to do

  • Switch off, catch the drip, and keep away from any wet socket or wiring.
  • Clean the filter with the power off.
  • Note from indoors where the pipe seems to end, for the technician and your neighbours.

Leave to the trained person

  • Clearing the drain, re-levelling the unit and any work on the coil or tray.
  • A pipe that has to be rerouted on the outside of the building.

Also asked

What if a clean filter doesn't stop it?

Then the drain, or the cause of any ice on the coil, needs a technician. LG blames ice on a dirty filter, and low gas is one more thing a technician can rule out. See the gas top-up story.

The water drips on the flat below. Whose job is it?

Generally yours to fix, and housing society guidance says the pipe must reach a designated drain. Your society's bye-laws decide the details, so ask the committee.

Where this came from

This story rests on those pages, opened or checked by 4 November 2026, and on no tests of our own. Maker pages speak for their makers, and rules and wiring differ by building, so check your own manual.