Why Is My Air Conditioner Leaking Water?

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Updated September 15, 2022

If you are new to the world of indoor temperature control, you may wonder how to stop an air conditioner from leaking water. Some of the best air conditioners, after all, leak water in certain scenarios. There may be a leak in your central air conditioner that you can’t find. Or, some elements may be causing a freon leak in your A/C. So why do AC units leak water and how to stop it? Keep reading to find out. 


  • There are many reasons why an air conditioning unit leaks, one of which is a clogged or dirty air filter.
  • Another thing to try to stop excess water is regularly checking and emptying out the drain pan of the unit as overfilled pans muck up the evaporator coils and condensate drain.
  • Also, keep the air vents clean and free from debris, removing any coverings like curtains or window sashes.

Why Do AC Units Leak Water?

Condensation is a natural part of the mechanism behind air conditioning, but leaking only occurs when something within this mechanism malfunctions, This malfunction could be related to the condenser, the fan, the motor, or even just the overall shape and design of the AC. Some machines even leak water when not in use, if you are learning how to store a portable air conditioner

Other good maintenance ideas are making your window A/C colder, learning what air conditioner filters do, how to remove mold from air conditioner coils, preventing bugs from coming through the window A/C, and finally, how to use a portable air conditioner without a window.

Insider Tip

Water leaks quickly lead to the formation of mold and mildew, so get on these issues as soon as you can.

How to Stop AC Units From Leaking  

There is more than one way to stop an AC from leaking, like when you are learning how big of a portable ac you need. It depends on the size of the machine, the specific problem, and the placement. Here are a few tips worth considering. 

Replace the AC Filters

Believe it or not, clogged air filters contribute to water leaks in an AC unit. So the first thing you should do if you find your AC leaking is to clean or replace the filters according to the manufacturer’s instructions to improve airflow and performance in your HVAC. Some filters can be simply cleaned with water, while others must be fully replaced. Once finished, check to see if it has alleviated your leaking problem. As a note, make sure you purchase and install an air filter designed to integrate with your specific AC unit. Generally speaking, clean or replace these filters once every three months. Make sure the filter installation is performed properly as well.

Check and Empty the Drain Pan

If the drain pan becomes overfilled, it will muck up the internal workings of the whole system, leading to water leaks. An easy way to nip this in the bud is to simply check on the drain pan and empty it if needed. 

Clean the Air Vents 

Clogged air vents also lead to leaky air conditioners, so do your best to keep these vents clean and clear from any and all debris. Avoid covering the vents with clothing, window sashes, curtains, or anything else, and perform a simple cleaning process once every 15 to 30 days or as indicated in the AC’s instructions.


How and why does water form in your air conditioner?

Water forms for many reasons, such as a clogged condensate drain, frozen evaporator coils, refrigerant leaks, a dirty air filter, water damage, a low refrigerant level, and more.

How do I know if my air conditioner is leaking water?

It should be fairly obvious, as you’ll see water, though the smell of mold or mildew is another indication that you have some kind of leak via a dirty air filter or another reason.

How do I stop my AC from dripping water in the future?

It’s all about maintenance and solving problems as soon as they occur, from refrigerant leaks to problems with the drainpipe, evaporator coils, and more.

STAT: Most modern air conditioning systems contain indoor and outdoor units. An evaporator coil is contained in the inside unit that cools the warm air as it blows over it to create a comfortable indoor temperature. (source)

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