Air Conditioning Units Leaks Water Top 3 Reasons

It must be frustrating when your air conditioning units start to leak water. When it happens, the first thing that most people do is to put a bucket below the leaking air-con and call for an air-con service. Not long after servicing the air con, it starts leaking again! Have you ever wonder what really is causing the problem? Is it really because your air conditioning units are just dirty? You are half right when you say that but there are more reasons to it. Here are some of the possible reasons why your air-conditioning unit leaks water.


# 1 - Drainage pipe clog with dirt

When your air conditioning unit is switched ON, it will bring the outdoor air to the air-con unit and convert the air into cool air. During this process, the outdoor dust will be stuck onto the coil fin. The dust will mix with the water in the coil fin, forming “dirt”. This dirt will then flow through the drainage pipe from the indoor air-con unit to the toilet. When there is too much dirt forming in the drainage pipe, it will start to clog and water will flow out through the indoor air-con instead.

This is a common problem and to solve it, it's easy. Just do an Air Conditioning Service (Chemical Flushing) and it will help to clean up the dust formed in the fin coil and clears the drainage pipe. Keeping your room clean and cleaning of air con filters will help to reduce the amount of dust sticking onto the air-con coil fin. This will prevent the drainage pipe from being clogged up too quickly.

#2 - Drainage pipe has no gradient

Water condenses when your air-con is switched ON. Drainage pipe is installed to allow the condensed water to flow from the indoor air-con to the toilet. Many air-con installers tend to install the drainage pipe too horizontally thus causing the drainage pipe to clog easily. It is better for the drainage pipe to be installed slightly slanted to allow the water to flow through the drainage pipe smoothly hence helps to push the dirt out.

#3 - Drainage pipe is too long

Do you realize that the air conditioning units that is located furthest from the toilet, where the drainage pipe drains away the water, usually leaks more often? Drainage pipe is usually installed in such a way that the main drainage pipe to the toilet will be shared among all the air-conditioners units. When all of your air-con is switched ON, dirt will formed at the main drainage pipe which caused the furthest air con to leak more often.

There are two ways in solving this problem. One way is to change the drainage pipe to one with a bigger diameter and this will minimize the chance of it being clogged up by the dirt. Another way is to install a additional drainage pipe from the air-con located in the furthest room to the toilet.


After reading the top 3 reasons stated above, you might realize that beside Problem #1, caused by daily usage, the rest are caused by improper installation. The installation phase is important and improper installation will cause the air-con to leak often at the later stage. Get a licensed air-conditioning company to do a proper installation for you!

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