Quick Answer
Aircond dripping water? Blocked drain pipe is the top cause. Also: dirty filter, low gas, or wrong installation. Clean filter first. Still leaking? Call a technician – it won’t fix itself.
Water dripping from your aircond indoor unit is one of those problems you should never ignore. It looks minor at first — just a few drops on the floor. But left alone, a small drip turns into a steady stream that damages your ceiling, stains your walls, grows mould in your room, and in the worst cases drips near electrical fittings where it becomes a genuine safety hazard.
The good news is that aircond water leaks are one of the most common and most fixable problems across Kuala Lumpur and Selangor. In most cases, the cause is identified and fixed on the first visit. You just need to know what you are dealing with.
This guide covers every common cause of an aircond water leak in Malaysian homes, what each cause means, what you can check yourself, and when the problem needs a professional to sort it out properly.
⚠ Switch Off Your Unit Right Away If:
Water is dripping onto or near any electrical socket, wire, or fitting. Switch the unit off at the wall isolator switch — not just the remote — and do not use it again until a technician has checked and fixed the problem.
Why Aircond Water Leaks Are So Common in Malaysia
Malaysia has one of the highest humidity levels in the world — consistently 70 to 90 percent across KL and Selangor throughout the year. Your aircond produces a lot of condensation as it cools the air. All that water must drain out through the drain pipe.
In humid climates like ours, algae, mould, and dust build up inside drain pipes far faster than in cooler countries. What takes two years to block a drain pipe in Europe might take six months in Puchong or Shah Alam. This is why regular servicing is not optional in Malaysia — it is the difference between a unit that drains properly and one that leaks all over your floor.
High-rise condo units face this problem more severely than landed homes. Enclosed spaces trap moisture, airflow is limited, and many condo units run 8 to 12 hours per day — producing far more condensation than the drain system can handle without regular cleaning.
The 5 Main Causes of an Aircond Water Leak
Blocked Drain Pipe — The Most Common Cause by Far
Your aircond removes moisture from the air as it cools your room. That moisture drips into a drain tray below the evaporator coil, then drains out through a pipe that exits through the wall. When that pipe gets blocked, water has nowhere to go and overflows into your room.
The blockage is almost always a thick, dark, jelly-like sludge made of algae, mould, and accumulated dust. Technicians across KL and Selangor see this on almost every service call. It is not a sign something is broken — it is a sign the unit has not been serviced regularly enough.
You can test this yourself by slowly pouring a small cup of water into the drain tray while the unit is off. If the water backs up instead of draining — the pipe is blocked.
The fix: A technician flushes the drain pipe with water pressure or a vacuum pump to clear the blockage completely. This is done during any standard service or chemical wash. It takes about 10 minutes and the leak stops the same day.
Signs the drain pipe is your problem
- Water dripping from the bottom of the indoor unit
- Water collecting in the drain tray and overflowing
- Unit has not been serviced in over 6 months
- Musty smell alongside the water drip
🔧 Needs a Technician
Dirty Air Filter Restricting Airflow
When your air filter gets clogged with dust, it restricts the warm room air flowing over the evaporator coil. Without enough warm air passing over it, the coil gets too cold and ice starts to form. When the unit defrosts, all that ice melts at once — producing more water than the drain tray can handle, which then drips into your room.
This is one of the few causes you can check and fix yourself right now. Open the front panel, pull out the filter, and look at it. If it is grey or dark brown and packed with dust — that is your problem. Wash it under a tap, let it dry completely, and refit it. If the filter was the cause, the leak should stop within an hour.
Signs a dirty filter is causing the leak
- Weak airflow from the unit alongside the water drip
- Ice visible on the indoor unit or copper pipes
- Unit has not had a filter clean in weeks or months
- Leak happens mostly when the unit first starts up
✓ Try DIY Fix First
🔍 Leak continuing after filter clean? Get a same-day diagnostic across KL and Selangor.
Low Refrigerant Gas Causing the Coil to Freeze
When your refrigerant gas level drops — almost always due to a slow leak — the evaporator coil cannot absorb heat at the right rate. It gets too cold and freezes over. You may actually see ice forming on the copper pipes or on the unit itself.
When the unit defrosts, all that ice melts at once. The drain system cannot handle that volume of water, so it overflows and drips into your room.
This is one of the more serious causes because low gas always means there is a leak somewhere in the system. Refilling the gas without finding and sealing the leak first is a waste of money — it will run low again within weeks. For a full breakdown of how this is diagnosed and fixed, see the detailed guide on aircond leaking water in Selangor.
Signs low gas is causing the leak
- Ice forming on the copper pipes or indoor unit panel
- Unit runs but room barely cools alongside the leak
- Hissing or bubbling sound from the unit
- Leak gets worse after the unit runs for a long time
🔧 Needs a Technician
Incorrect Installation Angle of the Indoor Unit
Your indoor unit must be installed at a very slight tilt toward the drain pipe side so condensation flows naturally into the drain tray and out through the pipe. If the unit was installed completely flat or tilting the wrong way, water sits in the drain tray instead of draining, fills up, and eventually overflows.
This is more common than most people realise — especially with cheaper installation jobs where the installer did not check the angle before fixing the bracket permanently. If your unit has leaked since installation — this is likely the cause. If the leak started suddenly on a unit that was previously fine — a blocked drain or dirty filter is more likely.
Signs incorrect installation is the problem
- Unit has leaked since it was first installed
- Water drips from one specific corner of the unit
- Drain pipe and filter are both clean but leak continues
- Unit was installed by a low-cost or uncertified installer
🔧 Needs a Certified Installer
Cracked or Damaged Drain Tray
The drain tray sits directly below the evaporator coil and collects all condensation before it drains away. In older units, this tray can crack or develop small holes over time. When that happens, water leaks through the tray itself rather than going down the drain pipe.
This happens more in units that are 8 years old or more. The plastic becomes brittle with age and repeated temperature cycling. A cracked drain tray needs replacing — a technician can usually do this during the same visit. The part costs RM50 to RM150 depending on the brand.
Signs a damaged drain tray is the problem
- Water leaking from bottom of unit even when drain pipe is clear
- Unit is over 8 years old
- Water visible inside the unit casing during inspection
- Leak continues immediately after a drain flush
🔧 Part Replacement Needed
Not sure which cause is your problem?
ACFix.my technicians carry camera drain scopes, gas pressure gauges, and full diagnostic tools on every visit. We find the exact cause on the first visit and give you a written price before starting any repair.
What You Can Check Yourself Before Calling Anyone
☑ 4-Step Self-Check for Aircond Water Leaks
1
Check and clean the air filter
Open the front panel, remove the filter, wash under tap water, dry fully, refit. Test the unit. If the drip stops within an hour — the filter was the cause.
2
Check for ice on the pipes or unit
Look at the copper pipes coming out of the indoor unit. If you see ice or frost — switch the unit off completely and let all ice melt before calling a technician to check gas pressure.
3
Check the outdoor unit is not blocked
A blocked outdoor unit causes the whole system to work harder, producing more condensation than normal. Make sure there is at least 30cm of clear space all around the outdoor unit.
4
Check when the unit was last serviced
If it has been more than 6 months, a blocked drain pipe is almost certainly the cause. Book a service — it will be identified and fixed during the visit.
How Much Does It Cost to Fix an Aircond Water Leak in Malaysia?
The cost depends on what is causing the leak. Here is what you can expect to pay in KL and Selangor in 2026.
| Cause of Leak | Fix Required | Estimated Cost |
|---|---|---|
| Dirty air filter | Self-clean at home | Free |
| Blocked drain pipe | Drain flush during service | From RM99 |
| Heavy drain blockage | Dedicated water leak fix | From RM130 |
| Mould and dirty coils | Chemical wash | From RM150 |
| Low refrigerant gas | Leak seal + gas refill | RM80 – RM250 |
| Wrong installation angle | Remounting by installer | RM100 – RM200 |
| Cracked drain tray | Part replacement | RM150 – RM300 |
| Unknown cause | Full diagnostic visit | RM88 diagnostic |
Always get a written price before any work starts. Every reputable service will confirm the price in writing after diagnosing the fault — before touching anything.
📍 Need a certified technician across Selangor? Same-day slots available.
How to Stop Your Aircond from Leaking Water in the Future
The single most effective thing you can do is stick to a regular servicing schedule. Most aircond water leaks in Malaysia are caused by blocked drain pipes — and blocked drain pipes are caused entirely by skipping servicing.
Every 2 to 4 weeks: Clean your air filter. Pull it out, rinse it, let it dry, refit it. This prevents dust from entering the drain system and keeps airflow at the level needed to prevent coil freezing.
Every 3 to 4 months: Book a standard aircond service. A trained technician will flush the drain pipe, clean the coils and blower, check gas pressure, and catch any developing blockage before it becomes a leak.
Every 12 months — every 6 months for condo units: Book a chemical wash. This deep-cleans the drain pan, internal coils, and blower wheel — removing the mould and algae at the source before they build up into a blockage.
💡 Related Reading
If your unit is also making unusual sounds alongside the water leak, those sounds often point directly to what else is wrong. Read this full breakdown: Aircond Compressor Noises — What They Mean and How Serious They Are
Frequently Asked Questions
Why is my aircond dripping water inside my room?
The most common reason is a blocked drain pipe. Over time, algae, mould, and dust build up inside the drain pipe until it gets completely blocked. When water has nowhere to drain, it overflows and drips into your room. Other causes include a dirty air filter, low refrigerant gas causing the coil to freeze and drip, or an indoor unit installed at the wrong angle.
Is an aircond water leak dangerous?
Yes, in some situations. Water dripping near electrical fittings, wiring, or plug sockets is a genuine safety risk and the unit should be switched off immediately. Water on your ceiling or wall causes structural damage, mould growth, and expensive paint damage. Even a small slow drip should be addressed within a few days — it gets worse, not better, on its own.
Can I fix an aircond water leak myself?
You can fix some causes yourself. Cleaning a dirty filter takes 10 minutes and sometimes resolves the leak. However if the leak continues after cleaning the filter, or if you see ice on the unit or pipes, you need a certified technician. A blocked drain pipe, low gas, and installation faults all require professional tools and training to fix properly.
How much does it cost to fix an aircond water leak in Malaysia?
A standard service including drain pipe flushing starts from RM99. A dedicated water leak fix starts from RM130. If caused by low refrigerant gas, a gas refill starts from RM80. A full diagnostic visit to identify the exact cause is typically RM88 with the price confirmed in writing before any work starts.
Why does my aircond only leak water sometimes and not all the time?
Intermittent leaking usually means the drain pipe is partially blocked — not fully blocked yet. Water drains slowly most of the time, but on hot days when the unit produces more condensation, the slow drain cannot keep up and overflows. It will become a constant leak as the blockage worsens. Address it now before it gets worse.
How do I stop my aircond from leaking water permanently?
Three things: a professional service or chemical wash to flush and clear the drain pipe, regular filter cleaning every 2 to 4 weeks, and a professional service every 3 to 4 months. In Malaysia’s humidity, drain pipes block faster than in cooler countries, so regular servicing is the only permanent prevention.
Ready to fix the leak today?
ACFix.my covers all areas across KL and Selangor. JKKP-certified technicians. Written price before every job. Same-day slots available. 30-day warranty on all workmanship.
Written by Umar Ansari, a JKKP-certified aircond technician who services, repairs, and installs all major brands across KL and Selangor every week. All causes, symptoms, and cost estimates in this article are based on real service experience. Last reviewed and updated: May 2026.
