Why is My Home Air Conditioner Leaking Water Inside

With warmer temperatures right around the corner, it’s time to start thinking about seasonal maintenance for your HVAC unit. And if you live in Houston Texas, you know that the summers can get pretty hot.

So, when you see water leaking inside from your AC unit, what do you do? Do you leave it alone and hope it evaporates, or do you shut down your unit and try to find the source of the leak?


How does water form in my AC unit?

Every AC unit contains evaporator coils, which cools down the warm air that blows from it. In return, condensation, or moisture, will form on the coil. The moisture then drips into the drain pan, which is connected to a condensate line that leads the moisture out of your home.

With this information in mind, here are a few ways that your AC unit can leak water:

The Condensate Line is Clogged

Clogged condensate lines are actually one of the common causes of water leakage. The pipe is prone to collecting large amounts of dirt, dust, mold and sludge, which can cause water to back up into the house.

If this happens, it’s important to unclog it as quickly as possible. There are various ways to unclog a condensate like including using a wet or dry vacuum. However, the best way is to hire a professional to suck out all of the blockages.

The Drain Pan is Rusted or Damaged

If you have an old air conditioner, chances are the drain pan is rusted through or damaged. If a drain pan is rusted or damaged, the water that it’s supposed to catch goes right through it. You’ll have to purchase a replacement drain pan.

The Condensate Pump is Broken

If an AC unit is installed in the basement, you need to keep an eye on the condensate pump. A condensate pump is what pumps the water outside of your home. If the pump breaks, however, then the water is trapped indoors and can start leaking. You will have to either repair the pump or replace it altogether.

Dirty Air Filters

If the air filter is dirty, it will block the airflow to the evaporator coil. This causes cause the coil to become too cold and ultimately, freezes over. After it melts, it can overflow the drip pan.

Always make sure to check the air filter to see if it has any dirt and dander in it. On a side note, depending on the season, you should always change your air filter every couple of months.

Low Refrigerant

If the refrigerant is slow, it lowers the pressure within the AC unit. Just like having a dirty air filter, the evaporator coil will freeze over and cause the excess water to pour onto the drain pan. You will notice that your refrigerant isn’t cooling properly or you hear a bubbling, hissing noise, which signifies a refrigerant leak. To rectify this problem, you’ll have to repair the leak itself, or depending on the intensity of the problem, replace the entire AC unit.

No homeowner wants to deal with a leaky air conditioner, especially on hot summer days. With that said, if a replacing a damaged drain pan or changing a dirty filter doesn’t solve the problem, it’s time to call in a professional.