Dealing With An AC Unit That Leaks Water

Posted on: 16 January 2017

If you live in Florida, Texas, or another southern state, then you may find your AC system invaluable. You likely run the system all year long and enjoy the cool air in your house for months on end. If you do this, then you may notice that the air conditioner leaks water sometimes. This can unfortunately cause a great deal of moisture to build in your home and mold to form in your basement. If you want to prevent these sorts of issues, then keep reading to learn how you can stop the AC unit from leaking.

Change The Filter

There are many different causes of water leaking from the AC evaporator unit that sits inside your home. If you constantly use your air conditioner and never turn it off, then you may not have a chance to change the filter. If the filter is dirty, then air may not be forced over the evaporator coil inside the unit. When air flow is low, then the evaporator coil can become too cold. Ice forms on the coil, and when the AC unit turns off, the ice melts. This can cause the condensate pan to overflow as water quickly drips from the coil.

If you cannot remember the last time you changed your AC air filter, then do so as soon as possible. If you are not very good about remembering to change it, then opt for a disposal fiberglass filter with a MERV rating in the 2 to 4 range. This is likely the same type of filter you have for your heating system. These filters remove the larger dust and pollen particles from the air without sacrificing airflow.

Filters with lower MERV ratings will allow more dust into your home, so you may want to purchase some disposal vent filters or a whole house air filtration system. If the extra dust does not bother you much, then you can simply vacuum a bit more as well.

Consider An Insufficient Drain

Air conditioners will create a great deal of moisture as they cool air. The AC unit will use an outdoor return or vent to supply the system with air. The air is forced over the evaporator coils where it is cooled, and the air is moved to your ducts. The air supply will usually start off warm and end up cool as it is forced from your vents. Warm air holds a lot of moisture, but cool air does not. As your AC system does its job, moisture falls out of the air and deposits on the evaporator coils. 

If you live in a humid area, then the cooling system will need to deal with several pints of water an hour. For example, an average or modest size AC unit can remove 3 to 4 pints of water an hour. All of this fluid collects in the drain pan and moves through a drain pipe. Some units use gravity to move the water out of the house, while others use a pump and a dedicated plumbing line to release all the moisture. 

If you use your AC unit a lot, then the drain may not be able to properly handle and remove all the water. If your AC system is newer or if you have always noticed a water dripping issue, then speak to your AC repair specialist about installing a larger drain pump on the drain line. This will help to move large quantities of water more quickly away from the system. Also, you can ask the professional to install a dehumidifier on the unit. A device installed on the supply duct or the main return of the unit is best. This will help to remove water from the air before it enters the air conditioner. The drain will then need to deal with less water overall. 

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