Why is my aircon leaking after servicing?
An aircon leaking soon after servicing usually has something disturbed in its drainage: the drain pan was refitted out of position, the drain pipe was loosened or kinked, or dirt washed off the coil settled in the drain pipe. It is normally a quick fix, but a leak with weak cooling may be a separate problem.
Key takeaways
- Timing tells you a lot: a leak within hours points to the drain pan or unit level, one a day or two later to dirt in the drain pipe.
- A few drops can be normal: leftover rinse water drains out of the coil in the first minutes after a wash.
- Do not open it yourself: drain pan clips and outlets crack easily and it complicates a warranty callback.
- It should be a warranty job: every iAircon service includes a 90-day warranty.
In the video above, Uncle Eric explains the top reason an aircon starts to leak water, which is worth knowing before you call anyone back.
How do I tell why it started leaking after servicing?
- Check if it is just rinse water. If a few drops fell in the first minutes and then stopped, that was water draining from the wash. If it drips steadily after the aircon has been cooling for a while, go to step 2.
- Note where the water comes out. From the side or front edge of the unit, go to step 3. From the bottom centre, go to step 4. Spitting out of the vents, go to step 5. From pipes, trunking or a false ceiling, go to step 6.
- Side or front drip, within hours: the drain pan is likely not seated, or the unit was knocked off level so the drain pan lost its fall.
- Bottom drip, within a day or two: dirt loosened during cleaning has probably settled in a bend of the drain pipe or at the floor trap.
- Water spitting from the vents: the evaporator coil may still be dirty deep in the fins, or icing up.
- Drips from pipes or ceiling: this is usually condensation from failed pipe insulation, not the servicing. See why aircon pipes drip from condensation.
- Leak plus weak cooling: this can be low refrigerant, which always means a leak somewhere in the sealed circuit, and it needs a separate check.
If you reach steps 3 to 7, switch the unit off and get it checked. Dripping right now? Message Luna on WhatsApp.
Is the leak from the servicing, or something else?
When and how it leaks | Likely cause | Caused by servicing? |
|---|---|---|
Within hours, from the side or front | Drain pan not seated, or unit off level | Likely |
Within a day or two, steady drip underneath | Dirt settled in the drain pipe | Likely |
Water spitting from the vents | Evaporator coil still dirty, or icing | Possibly |
Drips from pipes, trunking or false ceiling | Failed pipe insulation, or a drain pipe loosened during servicing | Possibly |
Leak plus poor cooling | Low refrigerant or very dirty coil; after a chemical overhaul, a flare joint (ours are under warranty) | Possibly |
What gets disturbed during servicing?
Dirt washed into the drain pipe
Cleaning loosens a lot of dust, slime and biofilm from the evaporator coil and drain pan. If the drain is not flushed afterwards, that dirt can collect in a bend of the drain pipe or at the floor trap and form a blockage within hours or days.
Drain pan not seated or clipped back
On many wall-mounted units the drain pan is removed for cleaning. If it goes back slightly out of position, or a clip is not fully engaged, water misses the outlet and runs out of the side or front.
Drain pipe loosened or kinked
The drain pipe connects to the drain pan outlet at the back of the unit. Moving the unit or pulling the drain pan can push the pipe off its spigot, or kink it behind the unit where you cannot see it.
Unit knocked off level
Removing panels and the blower fan means handling the unit. If it shifts on its bracket, the drain pan no longer slopes towards the outlet and water pools at the wrong end.
Coil only surface-cleaned
A quick spray clears the dust you can see but can leave sludge deep in the fins. Water then runs off the coil unevenly and gets blown out with the air. In bad cases the coil needs a proper deep clean rather than a rinse: the PowerJet deep clean in premium servicing, or a heavy-duty coil cleaner from S$30, advised on site when the coil's condition calls for it.
A problem that was already there
Not every leak after servicing is caused by it. A drain pipe that was already partly blocked, torn insulation or low refrigerant can show up the same week. A good technician tells you which it is rather than redoing the cleaning and leaving. The full list of causes is in our guide to why an aircon leaks water.
What should a proper service do to prevent leaks?
- Remove and clean the drain pan and blower fan, not just spray them in place. During premium servicing we take both out and clean them with PowerJet, and a chemical wash also takes them out and PowerJets them back to as-new.
- Flush the drain pipe after cleaning so loosened dirt does not settle in it.
- Pour water into the drain pan and check it flows out of the drain outlet.
- Refit the drain pan, pipe and panels, and check the unit is level.
- Run the aircon for a few minutes before leaving to check for drips.
What it costs
Situation | Price | What drives it |
|---|---|---|
Leak after our servicing | Free inspection and leak fix | Within 90 days of the service |
Drain pipe clearing (separate cause) | Quoted after the S$150 diagnosis | Access, whether the unit must be opened |
Chemical wash for a slimy fan and drain pan | S$120 per unit | Heavy-duty coil cleaner from S$30, if advised on site |
Pipe insulation replacement | Quoted after the S$150 diagnosis | Length of pipe, exposed or concealed |
Gas leak check | S$580 (1 to 3 units), S$880 (4 to 5 units) | Number of indoor units |
When to call a technician
Call straight away if the leak is steady, if water is reaching a wall, false ceiling or power point, or if the unit is also not cooling properly. If iAircon serviced the unit, it is covered by our 90-day warranty: WhatsApp us photos or a video of the leak.
For a new appointment you can book online in under a minute, or message Luna, our AI assistant, on WhatsApp any time.
Frequently asked questions
Is it normal for an aircon to drip a little right after servicing?
A few drops in the first minutes can be leftover rinse water draining out of the coil and drain pan. A steady drip once the aircon has been cooling for a while is not normal and means water is not reaching the drain properly.
Should the servicing company come back for free?
If the leak started straight after their visit, check their servicing warranty first. Every iAircon service includes a 90-day warranty, so if a unit we serviced starts leaking within 90 days, WhatsApp us photos or a video: the inspection and fixing the leak are free.
Can a leak after servicing damage my wall or ceiling?
Yes, if it is left running. Water soaks into plaster, paint and false ceilings below the unit and can leave watermarks or soft patches. Switch the aircon off and arrange a check as soon as you notice it.
Can I use fan mode while I wait for the technician?
Usually yes. Fan mode moves air without cooling the evaporator coil, so little or no new water condenses. If water still drips on fan mode, switch the unit off completely.
Will it leak again after my next service?
Not if the cause is fixed and the drain is tested before the technician leaves. If the same unit leaks after every service, the drain pipe may have too little fall or a weak point that needs repairing rather than just clearing.
Eric Lim, aka Uncle EricFounder of iAircon.Repair, now in its 10th year servicing aircons in Singapore. Every job is filmed, so you can watch the work on YouTube.
