Living in Petaling Jaya means dealing with humidity levels that average around 80% year-round. This moisture puts a massive strain on cooling systems.
We find that water leak calls make up nearly 40% of our total service requests across the Klang Valley. It is the single most frequent issue homeowners face.
Most leaks stem from straightforward causes that are easy to identify. Ignoring a drip can lead to wall damage, parquet floor warping, and mould growth that costs thousands of Ringgit to repair.
Our team at PJ Kool Aircond Service wants to help you troubleshoot before calling for help. Here are the five most common causes of water leaks and the practical steps you can take to fix them.
Cause 1: Clogged Drainage Pipe
This blockage is the primary reason for aircond leaks in Malaysia. Your unit acts as a dehumidifier while it cools. It pulls moisture from the sticky tropical air, condenses it on the cold coils, and sends it down a PVC pipe to a floor trap or outside drain.
Biological growth thrives inside these damp, dark pipes. We regularly clear pipes choked with a jelly-like substance known as biofilm. This sludge combines with dust to form a solid plug.
When the water cannot exit, it backs up. The drain tray eventually overflows and spills down your wall.
The Role of Biofilm and Dust
Research indicates that biofilm can begin forming within just a few weeks in high-humidity environments like Kuala Lumpur. Dust creates the structure for this slime to cling to.
Our technicians often find that units installed near kitchens or open windows clog faster due to airborne grease and pollutants.
DIY Fix
You can try to clear a minor blockage yourself. Locate the outlet of the drainage pipe, which is usually found in your bathroom or on a balcony.
Use a wet-and-dry vacuum to suck the debris out from the end of the pipe. This method is safer than pushing a wire up, which might puncture the flexible hose or push the clog deeper.
When to Call a Professional
Persistent clogs usually indicate that the sludge has hardened inside the drain pan itself. A standard vacuum cannot reach this area.
We recommend a professional chemical wash in these cases. This service uses a specialized chemical solution to dissolve the biofilm and flush the entire drainage system properly.
Cause 2: Dirty Air Filter
A dirty filter does more than just degrade air quality. It is a silent cause of water leakage that also inflates your TNB bill.
Dust buildup blocks the warm air from your room from flowing over the evaporator coils. Without this heat transfer, the coils drop below freezing point.
Ice begins to form on the fins. When the unit cycles off, that ice melts rapidly. The resulting volume of water overwhelms the drainage tray and spills over the sides.
The Energy Cost of Dirty Filters
Data from energy studies shows that a clogged filter can increase an air conditioner’s energy consumption by 5% to 15%. Your unit has to work harder to pull air through the blockage, leading to higher monthly costs.
We advise checking the filters monthly. If you hold the filter up to a light and cannot see through it, it is too dirty.
DIY Fix
Open the front panel and remove the mesh filters. Wash them gently in the shower with lukewarm water.
Let them air dry completely before putting them back. Putting a wet filter back into the unit can encourage mould growth on the coil.
When to Call a Professional
Clean filters might not stop the freezing if the evaporator coil itself is clogged with deep-set dirt. You will need a technician to perform a deep clean if the ice persists.
Cause 3: Low Refrigerant and Frozen Coils
Low gas levels are another common culprit for frozen coils. This might sound contradictory, but lower pressure actually causes the temperature of the cooling coil to drop drastically.
We often spot this issue when a customer mentions the air isn’t cold, followed by a sudden leak when they turn the unit off.
Identifying the Leak Signs
Refrigerant acts in a closed loop and does not evaporate over time. If the level is low, there is a physical leak in the copper piping or flare nuts.
You might notice oil stains around the pipe connections on the outdoor unit. This oil escapes alongside the gas and serves as a clear visual indicator of a leak.
DIY Fix
There is no safe DIY method for handling refrigerant leaks. Gases like R32 and R410A operate under high pressure and are mildly flammable.
When to Call a Professional
Turn the unit off immediately if you see ice on the copper pipes. Running the unit in this state can damage the compressor.
Our team provides a detailed diagnostic for this issue. We use pressure gauges to confirm the leak, weld or re-flare the connection, and top up the gas during our aircond repair service.
Cause 4: Broken or Cracked Condensate Pump
Many condominiums in Mont Kiara and KL City Centre use condensate pumps because gravity drainage isn’t possible in the building layout. These small mechanical pumps push water up into the ceiling void to reach the main drain line.
Mechanical failure is common after 2 to 3 years of heavy usage. The float switch inside the pump can get stuck, or the motor simply burns out.
Signs of Pump Failure
| Symptom | What It Means |
|---|---|
| Sudden overflow | The pump has stopped working entirely. |
| Gurgling noise | The pump is struggling to push water or sucking air. |
| Buzzing sound | The motor is jammed or failing. |
DIY Fix
You can check if the breaker for the aircond has tripped. Sometimes a power fluctuation disrupts the pump.
Tap the pump reservoir gently. This can sometimes dislodge a stuck float switch temporarily.
When to Call a Professional
Replacing a pump requires working with electrical wiring and plumbing simultaneously. We stock reliable brands like King Pump and Little Giant that are designed to handle Malaysia’s humidity and voltage standards.
Cause 5: Improper Installation
We frequently encounter installation errors in new developments where contractors rushed the job. The most critical factor is the gradient of the drainage pipe.
Water needs gravity to flow. If the pipe has no slope, or worse, an upward slope (back-flow), water will stagnate.
Another installation fault is poor insulation. If the copper pipes aren’t wrapped properly with Armaflex insulation, “sweating” occurs. This condensation drips from the pipes directly onto your ceiling plaster.
Signs of Installation Problems
- Leaks appear within weeks: New units should not leak.
- Dripping from the rear: Water flows backward away from the drain.
- Wet spots on the ceiling: Indicates pipe sweating above the plaster ceiling.
DIY Fix
Structural installation issues cannot be fixed with a simple patch. The unit or piping must be physically adjusted.
When to Call a Professional
You need a technician to re-level the wall plate or re-route the drainage piping. Our technicians carry spirit levels and proper insulation materials to correct these “cowboy” installations.
How to Prevent Water Leaks
Routine care is the best defense against leaks. Use this maintenance schedule to keep your unit dry and efficient:
- Bi-Weekly: Wash your air filters. This simple task prevents the majority of freezing issues.
- Monthly: Pour a cup of warm water down the drain pipe (if accessible) to test flow.
- Every 6 Months: Schedule professional maintenance. Our chemical wash service removes the deep grime that DIY cleaning misses.
- Yearly: Check the outdoor unit for debris or leaves that might block airflow.
When a Simple Fix Will Not Do
Water leaks can quickly escalate from a nuisance to a hazard. Water interacting with electrical components poses a short-circuit risk.
You should contact a professional if DIY cleaning doesn’t stop the drip. PJ Kool Aircond Service has served the Petaling Jaya community for over 15 years.
Our technicians troubleshoot leaks daily. We identify the root cause, whether it is a simple block or a complex part failure, and provide a clear price before starting work.
Book a service call with us today. Let us help you keep your home cool and dry.
Ahmad
Senior HVAC Technician
Senior HVAC technician with 15+ years of aircond repair experience in the Klang Valley.
