
Aircond Leaking Water? 8 Causes & Fixes Malaysia (2026 Guide)
Aircond leaking water in Malaysia? The 8 most common causes: blocked drain pipe, dirty filter, frozen coil, low refrigerant, tilted indoor unit, broken drain pump, damaged drip tray, full water tray. Fixes from RM 99.

Aircond leaking water in Malaysia is one of the most common AC problems. The 8 most common causes are: blocked drain pipe (40% of cases), dirty filter, frozen evaporator coil, low refrigerant, tilted indoor unit, broken drain pump, cracked drip tray, and full condensate tray. Most fixes cost RM 99-RM 350. Here is the full diagnosis and fix guide.
This guide is prepared by KL Renovator's HVAC Expert Team for Malaysian homeowners, condo residents, and offices dealing with aircond water leaks.
Quick answer — aircond leaking water in Malaysia
The most common cause of aircond water leaks in Malaysia is a blocked drain pipe (about 40% of cases). This is caused by algae, mould, slime, and dust buildup inside the drain pipe over months of use. The fix is a chemical flush of the drain pipe, which is included in KL Renovator's chemical wash service from RM 120 for 1.0-1.5 HP. Other common causes and fixes are detailed below.
The 8 most common causes and fixes
1. Blocked drain pipe (40% of cases)
Symptoms: Water dripping from the indoor unit, water stain on the wall below the AC, water pooling on the floor, musty smell.
Cause: Algae, mould, slime, and dust accumulate inside the 1cm PVC drain pipe over 6-12 months. The condensate water has nowhere to drain and overflows back through the indoor unit.
Fix: Chemical flush of the drain pipe. KL Renovator uses a high-pressure pump + chemical solution to clear the blockage. Cost: included in chemical wash (RM 120 for 1.0-1.5 HP) or as a standalone service (RM 80-150 per unit).
2. Dirty air filter (20% of cases)
Symptoms: Weak cooling, ice on the indoor unit, water dripping.
Cause: A clogged filter restricts airflow over the evaporator coil. The coil gets too cold, ice forms on it, and the ice melts into water that overflows the drip tray.
Fix: Clean the filter (you can do this yourself with warm water). For a full service, basic service RM 99 for 1.0-1.5 HP includes filter cleaning and coil inspection.
3. Frozen evaporator coil (15% of cases)
Symptoms: Ice visible on the copper pipe connections or on the indoor unit body, weak cooling, water dripping when ice melts.
Cause: Several possible reasons: low refrigerant (gas leak), dirty filter (see above), blocked coil, faulty thermostat, or running the AC below 22°C for extended periods.
Fix: Switch off the AC for 2-4 hours to let the ice melt. Clean the filter. If it freezes again within hours, you likely have a refrigerant leak — call KL Renovator for gas top-up (from RM 2.50/PSI) and leak check.
4. Low refrigerant (10% of cases)
Symptoms: AC takes longer to cool, ice on the indoor unit, water dripping, hissing sound from the outdoor unit.
Cause: Refrigerant leaks from loose connections, vibration damage, or corrosion. The reduced refrigerant pressure causes the evaporator coil to over-freeze.
Fix: Gas top-up (from RM 2.50/PSI for 1.0-2.5 HP) plus leak detection. If the leak is significant, repair the leak point first, then top up.
5. Tilted indoor unit (5% of cases)
Symptoms: Water dripping from one specific side of the indoor unit, water pooling on the floor under that side.
Cause: The mounting bracket has loosened over time, or the original installation was not level. The drip tray is tilted away from the drain pipe, so water flows to the wrong side and drips out.
Fix: Re-level the indoor unit. This requires removing the unit from the bracket, adjusting the bracket, and remounting. Cost: RM 80-150 for labour, or covered under workmanship warranty if installed by KL Renovator in the past 30 days.
6. Broken drain pump (5% of cases — ceiling cassette only)
Symptoms: Ceiling cassette leaking water, water dripping from the ceiling, water pump making unusual noise or not running.
Cause: Ceiling cassette units use an electric condensate pump to push water up and out (no gravity drainage). The pump motor can fail, the float switch can stick, or the pump chamber can get clogged.
Fix: Replace the condensate pump. Cost: RM 350-550 for the pump + RM 100-200 for installation labour. KL Renovator supplies and installs replacement pumps for all major brands.
7. Cracked drip tray (3% of cases)
Symptoms: Water dripping from a specific point on the indoor unit, visible crack or rust on the drip tray.
Cause: Age, corrosion (especially in coastal areas like Port Klang or Penang), physical damage during previous service.
Fix: Replace the drip tray. Cost: RM 150-300 for the part + RM 80-150 for installation. Common in older units (8+ years).
8. Full water tray (2% of cases — portable/window units)
Symptoms: Window unit or portable AC leaking water, no visible blockage.
Cause: Window units and portable ACs collect condensate in an internal tray that needs manual draining. If the tray is full, water overflows.
Fix: Drain the tray manually (usually a plug at the bottom or back of the unit). For window units, KL Renovator offers a permanent drain pipe modification for RM 100-200.
Quick self-diagnosis checklist
- Is the filter clean? (open the front panel and check)
- Is the indoor unit level? (use a spirit level or a phone app)
- Can you see ice on the coil? (shine a flashlight)
- Is the outside temperature very cold? (below 24°C may not need AC)
- When did you last service the AC? (6+ months = time for service)
- Does the leak happen always or only when it's humid? (humidity-related = drain issue)
What NOT to do when AC is leaking
- Don't keep drilling extra drainage holes — it doesn't fix the root cause.
- Don't pour bleach down the drain pipe randomly — it can damage seals and gaskets.
- Don't keep running the AC if it's frozen — switch it off for 2-4 hours first.
- Don't try to dismantle the unit yourself if you are not trained — call a professional.
- Don't put a bucket under the leak and ignore it — the leak will only get worse.
How KL Renovator fixes a leaking AC
- On-site inspection (RM 138 diagnostic fee, waived with same-visit repair).
- Identify root cause (drain blockage, refrigerant leak, tilted unit, etc.).
- Quote the fix clearly before starting work.
- Perform the repair (drain flush, gas top-up, re-level, replace parts).
- Test run for 30-60 minutes to confirm the leak is resolved.
- 1-month workmanship warranty on the fix.
Service coverage across KL & Selangor
KL Renovator serves Kuala Lumpur, Petaling Jaya, Shah Alam, Subang Jaya, Puchong, Klang, Ampang, Cheras, Kajang, Setia Alam, Rawang, Selayang and Batu Caves. We work on Daikin, Panasonic, Mitsubishi, Acson, York, Carrier, Midea, Haier, Toshiba, Hitachi, Samsung, LG, Sharp, Fujitsu, Gree, National, Hisense, Aux, TCL and Isonic for wall-mounted, ceiling cassette and window units only.
FAQ — aircond leaking water in Malaysia
Why is my aircond leaking water suddenly?
The most common cause is a blocked drain pipe (40% of cases). Algae and mould accumulate in the drain pipe over 6-12 months and block the condensate flow. The water backs up and drips from the indoor unit.
How much does it cost to fix a leaking aircond?
RM 99-RM 350 depending on the cause. Chemical wash to clear the drain pipe is RM 120 for 1.0-1.5 HP. Gas top-up is from RM 2.50/PSI. Re-leveling is RM 80-150. Drain pump replacement is RM 350-550.
Can I fix a leaking aircond myself?
You can clean the filter yourself. For drain pipe blockages, you can try pouring white vinegar down the drain pipe. But for persistent leaks, frozen coils, or gas issues, call a professional. KL Renovator diagnostic is RM 138, waived with same-visit repair.
Is a leaking aircond dangerous?
The water itself is not dangerous, but it can damage walls, ceilings, and electrical fixtures. Prolonged leaks can cause mould growth (which is a health hazard) and electrical short circuits if water reaches wiring. Fix it promptly.
Why does my aircond leak only when it rains?
High humidity during rain increases the condensate volume. If the drain pipe is partially blocked, the extra water can push past the blockage or overflow. Heavy rain can also push water back up the drain pipe if the outdoor end is not properly sealed.
How often should I service my aircond to prevent leaks?
Basic service every 1-2 months + chemical wash every 6 months keeps the drain pipe clear and prevents most leak causes. AMC customers get this automatically.
Why is my new aircond leaking water?
If a newly installed AC is leaking, the most common cause is a tilted indoor unit (bracket not level) or a drain pipe that was kinked during installation. Both should be covered under the installation workmanship warranty if installed by KL Renovator in the past 30 days.
Can a leaking aircond be caused by rain?
Heavy rain can cause water to enter the outdoor unit area and sometimes seep back through the drain pipe if the drain outlet is not sealed. KL Renovator uses proper drain traps to prevent this. If your drain is just a simple pipe out the wall, ask about a proper drain trap installation (RM 50-100).
Why does my ceiling cassette leak water?
Ceiling cassette units use an electric condensate pump. Common causes: pump failure (RM 350-550 to replace), float switch stuck, pump chamber clogged, or the pump's check valve failing. KL Renovator services all ceiling cassette pumps.
How long does it take to fix a leaking AC?
Drain pipe flush: 30-60 minutes. Gas top-up: 1-1.5 hours. Re-level: 30-60 minutes. Drain pump replacement: 1.5-2 hours. Drip tray replacement: 1-2 hours. Most leak fixes are done in a single visit.
Ready to book?
WhatsApp KL Renovator at +60182983573 if your aircond is leaking water. See our Fix: Aircond Water Leaking troubleshooting guide or book a Major Overhaul Service to fix it permanently. Diagnostic fee RM 138, waived with same-visit repair.
Definitions
Key terms in this guide, explained
Short, plain-language definitions of the terms used above — written by the technicians who do the work, not copied from a manufacturer brochure.
What is pump-down, and who pays if it is skipped?
Pump-down is how refrigerant is saved before a unit is taken off the wall: the technician closes the liquid valve, runs the compressor briefly so the gas collects in the outdoor unit, then closes the suction valve and disconnects the pipes. Skip it and the whole charge vents to atmosphere, so the reinstall needs a full recharge you then pay for.
Ask whether the quote for dismantling includes pump-down and a new flare set; those two items decide whether the reinstall cools properly.
What is the difference an overhaul makes to a blocked unit?
A chemical overhaul is the level above a chemical wash: the indoor unit is dismounted, dismantled into casing, blower wheel, drain tray and coil, and each part is soaked and scrubbed separately before reassembly and a leak test. It is the only way to clear a drain tray that has silted up or a blower wheel packed solid with mould. Published price starts at RM 420 for 1.0–1.5 HP.
Ask for an overhaul instead of another wash if the unit still drips or smells within weeks of a chemical wash.
HP — what is it measuring, and why do quotes ask for it?
HP is the informal Malaysian shorthand for cooling capacity, carried over from compressor horsepower. In practice 1.0 HP ≈ 9,000 BTU/h, 1.5 HP ≈ 12,000 BTU/h, 2.0 HP ≈ 18,000 BTU/h and 2.5 HP ≈ 24,000 BTU/h. Service, chemical wash and installation prices are all quoted against these bands, which is why the technician asks for HP before quoting.
HP is printed on the indoor unit's side label and on the outdoor nameplate — check there rather than guessing from room size.
Side-by-side comparison
Leak repair vs another top-up — where should the money go?
Refrigerant is not consumed by running the unit, so a top-up is only ever a temporary answer.
| What to compare | Top-up only | Find and repair the leak |
|---|---|---|
| How long cooling lasts | Weeks to months, depending on leak size | Years, if the joint is properly remade |
| Time on site | Under an hour | Longer — pressure test, then repair and recharge |
| Published price | RM 3.00 / PSI (R32) | RM 120 / leak |
| Risk if ignored | Compressor runs hot and under-lubricated | Removes the cause |
In short: One top-up on an old unit is reasonable. A second within twelve months means you are paying rent on a leak you have not fixed.
Quick answer
KL Renovator's practical answer: Aircond leaking water in Malaysia? The 8 most common causes: blocked drain pipe, dirty filter, frozen coil, low refrigerant, tilted indoor unit, broken drain pump, damaged drip tray, full water tray. Fixes from RM 99.
Reader FAQs
Why is my aircond leaking water suddenly?
The most common cause is a blocked drain pipe (40% of cases). Algae and mould accumulate in the drain pipe over 6-12 months and block the condensate flow. The water backs up and drips from the indoor unit.
How much does it cost to fix a leaking aircond?
RM 99-RM 350 depending on the cause. Chemical wash to clear the drain pipe is RM 120 for 1.0-1.5 HP. Gas top-up is from RM 2.50/PSI. Re-leveling is RM 80-150. Drain pump replacement is RM 350-550.
Can I fix a leaking aircond myself?
You can clean the filter yourself. For drain pipe blockages, you can try pouring white vinegar down the drain pipe. But for persistent leaks, frozen coils, or gas issues, call a professional. KL Renovator diagnostic is RM 138, waived with same-visit repair.
Is a leaking aircond dangerous?
The water itself is not dangerous, but it can damage walls, ceilings, and electrical fixtures. Prolonged leaks can cause mould growth (which is a health hazard) and electrical short circuits if water reaches wiring. Fix it promptly.
Why does my aircond leak only when it rains?
High humidity during rain increases the condensate volume. If the drain pipe is partially blocked, the extra water can push past the blockage or overflow. Heavy rain can also push water back up the drain pipe if the outdoor end is not properly sealed.
Reviewed by real technicians
KL Renovator's HVAC Expert Team
This article links back to the same field team that services wall-mounted, ceiling cassette and window units across KL & Selangor. Meet the 4 real technicians behind KL Renovator, see their experience, and review our service standards before you book.



