Water Leak in a Central Air Conditioner

Water

• All water found in a central air-conditioning system originates from accumulated condensation. A central air conditioner cools by blowing hot indoor air across cold Freon tubing. These tubes "sweat" from the humidity, just as a cold glass of water sweats in a humid room. The condensation drains down from the tubes to a pan and is piped outside your home. Any leaks or water issues in a central air conditioner occur somewhere in this process.

Condensate Pan

• The condensate pan, located inside the air handler, is a delicate design. It is constructed with a slight slope to ensure that all condensation drains through a drain in the center of the pan. If you have been working around the air handler, you may have bumped into the unit and tilted the pan. This will lead to localized leaks right around the air handler. Most central air-conditioning systems have user serviceable condensate pans, so consult the user manual to check whether the pan is draining properly.

Detached Drain Pipe

• The drain pipe that drains the condensate pan can easily be detached or damaged. It is typically PVC and will emerge from the air conditioner air handler and drain outside your home or into your gutter system. Ensure this drain pipe is properly attached to the pan drain and is not cracked or broken.

Clogged Pan or Pipe

• Condensate pan drains and their drain pipes can become clogged, causing a backup of water. Ensure the condensate pan drain is not clogged by using a pipe cleaner or piece of wire hanger to clean out the small hole. Often if a unit has been run without a filter for a prolonged period of time, clogs can occur. You may also want to run compressed air through the condensate drain pipe; check that it is draining properly by pouring a small amount of water through the pipe.