Why Is Water Leaking from My AC Unit?

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drip-drop-waterThere have been a few times when we’ve sent out plumbers to repair a home leak, only to discover a leak is actually coming from a homeowner’s air conditioner! Many people are surprised to hear about water leaking from their air conditioning system, as they didn’t know their air conditioner used water to operate. Here’s the thing: it doesn’t.

Today, we’ll explain how your air conditioner works in order to help you understand why water would leak from the AC unit. What’s important is that you schedule regular maintenance to detect these issues early and schedule AC repairs ASAP when you notice a problem. A leaky water heater can be quite destructive, costing thousands to repair your home!

Where does the water come from?

The water actually comes from the air in your home. There’s always some level of humidity—water vapor that takes up space in the air. You’ve seen that water vapor in the air condense (turn into liquid form) before. When you drink a glass of cold water on a warm day, you likely see condensation form on the outside of the glass.

The same scientific process happens as warm air moves over a cool condenser coil in your air conditioning system. Refrigerant moving through the evaporator coil absorbs heat from the air in your home blowing over it. This coil cools down in return, which allows it to dehumidify. Water vapor collects on the coil, and a condensate drainage system is in place to help it drain.

What can go wrong with a condensate system?

Normally, water drips off of the indoor evaporator coil into a tray underneath the coil unit. The tray is positioned at an angle, allowing water to drip into a hole at the bottom edge of the tray that leads to a condensate drain—a pipe that leads outdoors.

Unfortunately, this drainage system may fail you when you really need it.

  • The drainpipe can clog with dirt and debris, allowing water to back up and overflow from the tray.
  • The tray may move out of place, or it might not be positioned properly in the first place.
  • The indoor coil can freeze when it doesn’t get enough airflow. When it thaws all at once, the condensate drain might not be enough to keep water from spilling out into the home.
  • You might have a particularly humid home and require a condensate pump to help move water along.

How can you prevent AC leaks?

You can prevent your air conditioner from leaking in a couple of ways.

  • Change the filter regularly to keep air flowing and prevent the indoor coil from freezing.
  • Schedule regular maintenance. Technicians can clean out your condensate line during routine air conditioning maintenance at the beginning of the season if they notice a clog.
  • Only allow professionals with plenty of experience to install a new AC system. Often, a leak occurs because a condensate system was not set up right in the first place.

What should you do when you notice a leak?

If you notice a leak from the area of your air conditioner, it’s important to act fast. Turn off the air conditioner ASAP and call a technician for service. In the meantime, if you can access the leak, soak up as much water as you can to prevent water damage and mold growth.

For air conditioning service in Blaine, MN, reach out to Air Mechanical, Inc. now!


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