Waking up to a puddle under your aircon, or water dripping onto your floor, is one of the most common aircon problems in Singapore homes. The good news is that most leaks have simple causes and can be fixed quickly. This guide explains why your aircon leaks, what you can safely check yourself, and when it’s time to call a professional.
Why Is Your Aircon Leaking Water?
Your aircon removes moisture from the air as it cools your room. That water is meant to collect in a drain tray and flow out through a drainage pipe. A leak means something is stopping that process.
1. Blocked drainage pipe
This is the most common cause. Over time, dust, algae and slime build up inside the drain pipe. The water can’t flow out, so it backs up and drips from the indoor unit. Singapore’s warm, humid climate makes this buildup happen faster.
2. Dirty air filters
Clogged filters restrict airflow. This can make the evaporator coil too cold, causing ice to form. When the ice melts, more water drips than the drain can handle.
3. Dirty evaporator coil
Dust and grime on the coil also reduce airflow and can lead to freezing and overflow.
4. Low refrigerant level
If refrigerant (gas) is low because of a slow leak, the coil can freeze and then drip heavily when it thaws. If this is the cause, topping up alone isn’t enough, because the leak has to be found and fixed. See our aircon gas top-up service for details.
5. Poor installation or a tilted unit
If the indoor unit isn’t level, or the drain pipe has a bad slope or a kink, water won’t drain properly. This is more common in newly installed units or after renovation work.
What You Can Check Yourself
Before calling anyone, these safe checks can help you understand the problem:
- Turn off the aircon if water is dripping, to avoid damage to your floor, furniture or electrical items.
- Look at the filters. If they’re covered in dust, they likely need cleaning.
- Check for ice on the indoor unit or pipes. If you see it, switch the unit off and let it thaw before using it again.
- Look at the drain pipe outlet (usually outside or in a bathroom or balcony). If little or no water comes out while the aircon is on, the pipe may be blocked.
Please don’t open the unit or poke into the drain pipe with sharp objects. You could damage the unit or hurt yourself.
When to Call a Technician
Call a professional if:
- Cleaning the filters doesn’t stop the leak
- The leak keeps coming back
- You see ice buildup repeatedly
- You notice a hissing sound, an oily residue or weak cooling, which can point to a refrigerant leak
- Water is dripping near electrical outlets or onto the ceiling
A standard aircon servicing visit includes cleaning the filters and coils and flushing the drainage line, which fixes most minor leaks. For heavy buildup, an aircon chemical wash may be needed. If a component has failed, you may need aircon repair.
How to Prevent Aircon Leaks
- Service your aircon regularly, about every 3 to 4 months for most homes
- Clean the filters every few weeks if you use the aircon daily
- Avoid running the aircon with doors and windows open, which creates extra condensation
- Book a check if you notice slower cooling or musty smells, which are early warning signs
Regular servicing is far cheaper than fixing water damage to your ceiling or flooring. You can book aircon servicing in Singapore here and have the drain line checked and flushed at the same time.