Our team at Coolbest Aircon Servicing was founded with a mission to deliver reliable, high-quality cooling solutions to communities across Singapore at affordable rates. An aircon leaking water is a direct distress signal that demands an immediate response — our aircon repair team handles drainage leaks every week across HDB, condo, and landed homes. A delayed reaction can lead to warped parquet flooring and toxic mould growth within days.
We will help you identify the problem quickly and prevent expensive repair bills.
You face potential fines of up to S$1,000 from the National Environment Agency (NEA) if your dripping unit becomes a public nuisance. This guide reveals the exact causes of aircon leaks and provides fast troubleshooting steps.
Emergency Steps (Do This First)
Our emergency protocol is designed to save your property from immediate water damage. If water is actively dripping from your unit, you must stop the flow immediately. Shutting off the power protects your expensive electronic components from a permanent short circuit.
We recommend following these exact steps to secure the area before doing anything else.
- Power off the aircon at the remote and the main circuit breaker.
- Put a towel or bucket underneath to protect your flooring.
- Check the wall and ceiling for any damp spots or structural damage.
- WhatsApp us at +65 9182 5233 with a clear photo of the leak.
Our technicians cannot stress enough the danger of turning the machine back on. Do not run the aircon again until a professional has checked the system. Running a compromised unit introduces extreme risks to your property and wallet.
- Water soaking into walls requires replastering that can cost over S$300.
- Short-circuiting the printed circuit board (PCB) demands a S$300 to S$500 replacement.
- Mould growth behind the wall triggers expensive remediation services.
- Ruined parquet flooring replacement often exceeds S$1,500 per room.
Cause 1: Blocked Drain Pipe (70% of Cases)
Our service data shows that a blocked drain pipe is the leading cause of indoor water leaks in Singapore. Condensate water normally drains through a flexible polyvinyl chloride (PVC) pipe from the indoor unit to an outside gully. Local humidity causes thick biofilm and jelly to accumulate inside these pipes rapidly.
- Symptoms: Drips will worsen significantly after the aircon runs for 20 minutes or more. The water usually drips steadily from the bottom edge of the indoor unit.
- Fix: A professional drain flush during standard servicing takes just 10 minutes and typically costs S$40 to S$60.
- Temporary Solution: A wet and dry shop vacuum placed on the outdoor drain outlet can sometimes clear the blockage. We strongly advise booking a proper chemical wash if the blockage returns frequently.
| Drainage Status | Water Flow Behaviour |
|---|---|
| Healthy Pipe | Steady drip from the outdoor drainage outlet. |
| Blocked Pipe | No water outside, but heavy dripping inside the room. |
Cause 2: Frozen Coil Thawing
Our maintenance records show frozen coils usually happen due to severely dirty fins or a low refrigerant level. When the fan coil freezes, a massive amount of ice builds up behind the plastic casing. This ice melts rapidly when you switch off the aircon, and the sudden rush of water overflows the internal drain pan. For more context, read our guide on aircon blinking light & error codes.
- Symptoms: The unit drips heavily right when you switch the aircon OFF, rather than while it is running. Visible white frost forms on the copper pipes during operation.
- Fix: Standard servicing resolves the issue if the fins are simply blocked by dust. A gas top-up and leak repair are mandatory if the system lacks refrigerant.
- Warning: We urge you not to ignore a frozen coil, as the extreme strain can destroy your compressor and result in an S$800 replacement bill.
Cause 3: Tilted Mounting
Our installation team ensures aircon indoor units are mounted with a very slight tilt toward the internal drain outlet. Gravity cannot pull the water away effectively if the mounting bracket shifts out of alignment. This issue frequently occurs after heavy nearby renovation work or due to old, rusted brackets.
- Symptoms: The unit drips from the side opposite the drain pipe or from unexpected corners. The leak appears in the exact same spot every time.
- Fix: Re-leveling the unit requires loosening the wall bracket and carefully re-adjusting the angle. This specialised repair visit typically costs S$80 to S$120.
- Warning: We warn against attempting to bend the plastic casing yourself, as you will likely snap the mounting clips.
Cause 4: Drain Pump Failure (Cassette and Ducted Units)
Our commercial clients often face this issue because ceiling cassette units rely entirely on a mechanical drain pump. Gravity drainage is impossible for these high-end residential and commercial systems. These pumps fail when their internal float switches jam with dirt or algae.
- Symptoms: Water drips directly from the ceiling grille or pools dangerously inside the false ceiling void. You might hear an unusual buzzing sound or complete silence where the pump noise used to be.
- Fix: Replacing a faulty drain pump generally costs S$200 to S$350. Brands like Daikin and Mitsubishi Electric require specific original equipment manufacturer (OEM) pumps.
- Note: We handle this strictly as a dedicated repair task, not a standard servicing job.
Cause 5: Full or Cracked Drain Pan
Our replacement logs indicate that plastic drain pans become brittle and crack after 5 to 10 years of constant exposure to cold water. The internal drain pan catches all the condensation before funneling it into the PVC pipe. A deep crack means water will bypass the drainage system entirely and flood your wall.
- Symptoms: Heavy dripping returns within just a few days of a professional drain flush. You will see stagnant water pooling inside the unit when you lift the front cover.
- Fix: Deep cleaning the pan during a chemical wash clears out hardened biofilm. You must replace the drain pan entirely if the plastic has cracked, which costs between S$150 and S$250.
- Trunking Leaks: Our diagnostic checks uncover worn Armaflex insulation around the copper trunking that mimics a leaking unit. Replacing this worn trunking insulation costs around S$150.
Diagnosing By Timing
Our triage process relies heavily on knowing the exact moment your unit starts dripping. Observing the timing helps technicians bring the correct spare parts to your home immediately. This preliminary data speeds up the repair process significantly.
| When It Drips | Likely Cause |
|---|---|
| After 20+ min of running | Blocked PVC drain pipe |
| When you switch OFF | Frozen fan coil thawing rapidly |
| Any time, same spot consistently | Tilted wall mount bracket |
| At the ceiling grille | Failed mechanical drain pump |
| Returns within days of flush | Cracked or heavily fouled drain pan |
What to Check Before Calling
Our diagnostic team appreciates when clients provide specific details upfront to help pinpoint the issue. Performing a few rapid checks can save you time and provide valuable information safely. You can gather these clues without opening the main electrical compartments.
- Is the outdoor drain actually draining? Go outside and look directly at the drain outlet. A completely dry pipe while the machine runs confirms a major internal blockage.
- Is the aircon level? Do a quick eye-check of the indoor unit. An obvious tilt indicates a serious mounting bracket failure.
- Is the filter clean? A clogged mesh filter chokes airflow, causing the system to freeze and subsequently drip.
- How old is the unit? Systems older than 7 to 10 years are highly prone to cracked plastic drain pans.
When It’s Servicing, When It’s Repair
Our pricing structure is completely transparent so you understand the difference between a service and a repair. A simple blockage requires standard cleaning, while broken parts demand technical replacements. We resolve about 70% of our dripping aircon calls using a highly effective standard servicing drain flush.
- Servicing (S$50/unit): Clears a blocked drain pipe, which is the most frequent cause of water leakage.
- Repair (S$80 diagnosis + parts): Addresses frozen coils, tilted mounts, broken drain pumps, or cracked pans.
The remaining 30% of cases need a specific repair visit to swap out failing components. WhatsApp us a 10-second video of the leak, and our experts will diagnose the problem instantly.
Book Service
Our scheduling system is designed to get a technician to your door as quickly as possible. Taking prompt action is the only way to prevent expensive water damage to your property. Delaying a fix will only increase the final repair bill and risk regulatory fines.
- For a simple blocked drain: book servicing S$50/unit
- For anything else: book repair, from S$80 diagnostic
Or WhatsApp +65 9182 5233 directly.
Most aircon leaking water emergencies get an expedited same-day or next-day slot to stop the damage fast.
We are ready to restore your comfort today.
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