Air Conditioner Condensation Drain Line Cleaning Air Conditioner Condensation Drain Line Cleaning Learn how to clean your air conditioner condensation drain line. TranscriptHi, I’m Lance with Invitation Homes. And today we’re going to talk about monitoring and cleaning your air conditioner condensation drain line. A clogged condensation drain line can cause a huge costly mess in your home, but this can be easily avoided by following a few simple steps. First, locate the air conditioning air handler unit inside your home. There are many brands, but it might look something like this. You might find it in a closet, garage, your basement, or even your attic. You’ll notice a drain line, usually a white PVC pipe exiting the unit similar to this one. This line carries the water created by condensation from the AC unit to the outside of your home. If this line becomes clogged, the overflow water will end up draining into your home which could potentially cause damage to your possessions.