Why do Aircon Leak water or Drip Water and How to Check it out?

Why is My Home Air Conditioner Leaking Water Inside?

This is the common question we get in Singapore during summer season. “Why is my AC leaking inside my home? In this article we will discuss why is this caused and how can we prevent this from happening.

But first, you need to turn off your aircon to prevent further damage to your floor and walls.

Before trying to understand the reasons for this happening, let’s understand how water and aircons are related.

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Air conditioner working cycle:

1. AC will have condenser which compresses the refrigerant gas, and the passed through the fins of the condenser

2. This will cause condensation (moister) on the evaporator coil

3.  Air flowing over the coil gets cold, and the moisture precipitates over the coil

4. A drain pan placed below the coil collects the water and discharges it through the drainage pipe


With all the above in mind, below are the common causes of water leakage from the air conditioner 

  • Clogged air filters: Clogged filters restrict airflow. If a filter is clogged, there is little air flowing over the chilled evaporator coil. The coil is not able to exchange enough heat and overcools. This causes the formation of ice, which may cause water to drip through the length of the indoor unit.
  • Clogged drain pipe: If the connection between the drain pan and drain pipe is clogged, the pan may overflow, causing water to drip for the aircon.


Alternatively, if the drip pipe is clogged with debris, it may not be able to discharge the water before the drain pan overflows.

  • Indoor unit orientation: The wall-mounted aircon unit should ideally be horizontal. If it is not mounted horizontally, the tilt can cause the water drain pan to overflow at the tilted side.
  • Drain pipe height: The drain pipe should have a vertically downward orientation. Any loop towards the upper side would require pressure to force the water out of the pipe. If this is the case, the accumulated water in the drain pan may not be able to pressurize water to clear the loop. In this case, your aircon would drip.
  • Refrigerant level: The system must have a recommended level of refrigerant. Deviation of pressure towards the higher or lower side can create problems. Water drips from the aircon in case of low refrigerant pressure. Low refrigerant pressure causes the gas to over-expand at the evaporator. Expansion of air causes cooling. In this case of low pressure, the evaporator coils’ temperature falls below the freezing point, and ice begins to form. Water drips when this accumulation becomes huge, and air circulates over the mass of ice. Depending on the severity of the refrigerant leak you’ll either repair the leak or replace the whole AC unit. If you need a new one, read our article, AC Repair or Replace
  • Cracked or corroded drain pan: If the drain pan is cracked, or corroded, the pan would leak, and water would drip down the indoor unit. In case the connection between the drain pan and pipe is improper, a similar situation could arise.


Locating the cause of the leak

You may be able to locate the cause of the water leakage. There is, however, only one that you could fix manually.

  • Check the airflow at the vent and inspect the air filters
  • Lift the front hood of the aircon and see if the evaporator is dirty, or is having ice formation
  • Check how much water is being discharged from the drain pipe.

Based on these conditions, you may figure out what is the reason of water leaking in your home. Cleaning the filter is the only thing you can do yourself. A professional aircon technician can do the other fixes.

To prevent problems like this, it is recommended that you get your aircon serviced professionally. Book the services of a competent aircon servicing company so that you can remain worry-free. MCL Aircon provides quality installation, aircon servicing, aircon repair solutions at competitive prices in Singapore. MCL Aircon serves in all areas of Singapore. The staff is well-trained professionals who perform a quality job every time. MCL Aircon is reliable aircon servicing company in Singapore providing 24 7 booking service.