Split AC dripping water inside or icing up? Usually a blocked drain or filter — and a bucket won’t fix it

First: the electrics, then the wall and floor

If water is landing on or near a socket or extension lead, don’t touch it or pull the plug: switch off the breaker first (the main one if you’re not sure which). If the water is well away from electrics, turn the AC off and switch it off at the breaker. Move electronics, rugs and furniture from under the unit, put down a towel or container to catch the drips, and dry the wall. Don’t open the front panel or touch the filter while the AC is connected to power.

Where does the water come from?

When room air passes over the cold coil inside the indoor unit, the moisture in it turns into droplets, the way a cold glass “sweats”. The droplets fall into a tray under the coil and run downhill through the drain hose until they leave the house. How much water there is depends on how humid the air is. Anything that cuts that path, or sends water down faster than the tray can hold, brings the water into the room.

The usual causes

• The drain line or tray is blocked with dust and slimy build-up. Riyadh dust comes in with the air, mixes with the water, and over time closes the path.
• A clogged filter or dirty coil: less air passes over the coil, so it gets too cold and ices up, then the ice melts all at once and the tray can’t hold it.
• The drain hose is kinked or crushed, runs uphill instead of down, or its end sits in water or inside a closed container.
• The indoor unit isn’t level or tilts away from the drain side, so water collects at one end of the tray and spills out the front. Common after a new installation or after the AC was moved.
• Low refrigerant from a leak: the coil can ice up even with a clean filter. It usually weakens cooling too, which our “AC running but not cooling” guide covers.
• A cracked or broken drain tray, which leaks no matter how clean the line is.

Three checks you can do yourself

1. The filter

   With the power off, open the front panel and slide the filter out. If there’s a layer of dust, rinse it in lukewarm water without harsh cleaners, dry it in the shade, not in the sun, and make sure it’s fully dry before refitting. A clean filter restores the airflow that keeps the coil from icing.

   You can check it
2. The drain hose outside

   Follow the thin hose that comes out through the wall. If the hose disappears into a pipe in the wall, that’s a technician’s job. If the water is well away from any electrics, run Cool for a while and look: is water coming out? Is the hose kinked or crushed under something? Is its end sitting in water, inside a closed container, or plugged with mud or insects? Straighten any kink and leave the end free above the water, and don’t push wire or anything sharp into it. In dry weather only a little water comes out, and that’s normal.

   You first, then a technician
3. Is there ice?

   Look at the coil and the pipes. If there’s ice: switch off Cool and run the AC on Fan until the ice has melted completely, with a towel underneath because more water comes out while it melts. Don’t chip the ice off by hand or with a tool — the coil is thin and bends easily, and the pipes can be scratched or punctured.

   You can check it

A bucket or towel under the AC protects the floor until it’s sorted, but don’t treat it as the fix. Water that overflows can also run down the wall behind the unit where you can’t see it.

Where is the water coming out? That points to the cause

If the checks didn’t stop the dripping, watch where the water comes from and when it starts:

1. Water comes out of the front of the unit or from under the louvres

   Likely cause: The tray is full and overflowing: a blocked drain, or the unit tilts forward

   You first, then a technician

2. Dripping starts after ice appears on the coil or pipes, or after you switch the AC off

   Likely cause: Melting ice overflowing: a clogged filter, or, if the filter is clean, a dirty coil or low refrigerant

   You first, then a technician

3. Drips from the pipe side or from the wall under the unit

   Likely cause: A loose or cracked drain hose joint, or damaged pipe insulation letting water condense on the pipes

   Needs a technician

4. The AC drips in the room, but nothing comes out of the hose outside even though Cool has been running a while

   Likely cause: Water isn’t reaching the hose: a blocked line, a kinked hose, or its end is under water

   You first, then a technician

5. Dripping started after a new installation or after the unit was moved

   Likely cause: The unit’s slope or the way the drain hose was fitted

   Needs a technician

Why Dry mode and a higher temperature aren’t a fix

Some pages tell you to switch the remote to Dry and raise the temperature. The dripping may ease because the AC is cooling less, but the cause is still there: Dry mode itself pulls moisture out of the air, and that water goes to the same tray and the same blocked line. If the cause is a clogged filter or low refrigerant, the ice can come back, especially once you return to normal cooling in the heat. A blocked line needs clearing, not a different setting on the remote.

What a technician checks