Why is the AC leaking water inside?
AC dripping into the room or onto the false ceiling? The usual causes, seven safe steps, what a technician does, and typical UAE prices.
An AC leaks water inside when the condensate it pulls from the air cannot leave through the drain line. The usual causes are a blocked drain line, dirty filters or coils that freeze and then overflow, a unit that is not level, or a cracked drain pan or loose pipe. Most leaks are fixed during a service with drain flushing, which costs about AED 150–400.
Normal dripping or a leak?
An AC removes a lot of moisture from the air, especially in humid coastal weeks in late summer, and that water has to go somewhere. Some dripping is normal:
- water dripping from the drain pipe outside, or from the outdoor unit of a split system;
- more water than usual on very humid days.
It is a problem when water drips from the indoor unit into the room, runs down the wall, or leaves stains on the gypsum false ceiling under a ducted or concealed unit. These need quick action: water soaks into gypsum board and paint fast, and repairing a ceiling can cost more than fixing the AC.
Find the likely cause
| What happens | Likely cause | Usual fix |
|---|---|---|
| Steady drips from the indoor unit, worse after hours of use | Blocked drain line (dust, slime, algae) | Drain flushing during a service |
| Ice on the coil or pipes, then a sudden gush of water | Dirty filters and coil, or low gas | Cleaning; leak check if it continues |
| Water from one end of a wall-mounted unit only | Unit tilted away from the drain side | Re-levelling the bracket |
| Wet patch or stain on the false ceiling | Overflowing drain pan of a ducted, concealed or fan coil unit | Cleaning the pan and drain through the access panel |
| Leak right after installation or a move | Wrong slope, kinked pipe or loose connection | Installer corrects it, ideally under warranty |
| Leak continues after cleaning, unit level | Cracked drain pan, loose pipe or a blocked building drain | Part replacement or building maintenance |
What can be done now
These steps are safe and take about 20–30 minutes. The unit cover and wiring stay closed.
- Switch it off. The remote is enough, unless water is running near a socket or wiring: then the breaker is safer, and the plug should not be touched.
- Protect the room. Wipe the water, move furniture and electronics away, and put a towel or bucket under the unit.
- Let any ice melt. With frost on the coil or pipes, the unit stays off, or on Fan mode, until it has melted completely.
- Wash the filters. Clean filters keep the coil from freezing.
- Check the drain pipe outside. Where the pipe ends on a balcony or wall, its end should be open, not kinked, and not blocked by sand, leaves or insects.
- Look at the slope. A wall-mounted split should be level or slope slightly toward the side where the pipe exits.
- Test for an hour. If water still drips inside, the unit should stay off until a technician checks it.
Bleach or chemical cleaners should not go into the drain, and wires or sticks should not be pushed into the pan. They can crack it or push the blockage deeper.
What a technician does and what it costs
Most leaks are fixed in one visit: the technician cleans the filters and coil, flushes the drain pan and line, checks the slope and runs the unit for a while. Typical prices in the UAE:
| Service | Typical price |
|---|---|
| Standard AC cleaning with drain flushing | AED 150–250 per unit |
| Drain line unblocking and pan flush (separate job) | AED 200–400 |
| Deep coil cleaning (heavy dirt, musty smell) | AED 300–700 per unit |
| Leak detection, repair and gas recharge | AED 600–1,200 |
If the coil freezes again after cleaning, a leak check is the next step, because low gas also causes freezing. If the unit is also not cooling well, see the guide on an AC not cooling. Water damage to the ceiling is a separate job: gypsum and false ceiling companies repair the boards once the leak is fixed.
Apartments and towers
In many buildings the AC drain connects to a shared drain pipe. If the unit is clean and level but water still backs up, the blockage may be in the building pipe, which is usually the building management's job. Fan coil units in district cooling buildings are often serviced by the building's facility team, so a call to them comes first. A work permit and allowed work hours are worth checking before a private technician comes, so the visit is not turned away at reception.
Stop it from coming back
- Wash the filters every 2–4 weeks, and every 2 weeks in summer.
- Book a service every 3–6 months, with drain flushing every time. The schedule is in the guide on how often to clean an AC.
- Check the outside end of the drain pipe after sandstorms and rare heavy rain.
- After a new installation, watch the unit for the first week and report leaks to the installer while the warranty applies.
If the filters and drain pipe look fine and water still drips, the problem can be described once on khalasna to get up to 5 quotes from AC repair companies, with the question of whether drain flushing and a test run are included in the price.
Frequently asked questions
Is a leaking AC dangerous?
The water itself is condensate, but it becomes a risk when it reaches a socket, an extension cord or wiring. In that case the unit should be switched off at the breaker and the area kept dry until a technician checks it.
Why does the AC leak only on humid days?
Humid air means the AC removes more water, so a drain line that is partly blocked or badly sloped overflows only on those days. Flushing the drain and checking the slope usually solves it.
Why is a new AC leaking water?
A leak soon after installation usually points to a wrong slope, a kinked pipe or a loose drain connection. The installer should be contacted quickly, because this is normally covered by the installation warranty.
Who fixes a leak from a fan coil unit in a chiller building?
Usually the building's facility management, because the fan coil units and their drains are part of the building system. The tenancy contract or the building rules say what tenants may arrange themselves.