AC Drain Line Clogged? Here’s What To Do

AC Drain Line Clogged? Here’s What To Do

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AC Drain Line Clogged? Here’s What To Do

An AC drain line may be called a condensate drain or a condensate line, but whatever name you give it, it’s an important part of your home’s AC system. The condensate drain line functions to remove condensation away from the evaporator coil. If the AC drain line is clogged, the water won’t drain or cool properly, and may even freeze internally. If this happens you’ll have even bigger issues like no air conditioning at all. 

If you suspect you may have an AC drain line clog, there are signs you can look for. Of course, the best move to make may be a call to a trained HVAC technician in Vail Valley like those employed by Climate Control Company.


  • You see standing water around your indoor or outdoor AC units.
  • If you smell a musty odor around your indoor unit or coming from the AC vents.
  • The AC unit isn’t cooling your home as before.
  • The unit is short-cycling, that is it shuts off before reaching the set temperature.
  • The outdoor evaporator coils are frozen.

If any of these indicators are present, you could attempt to open the clogged AC drain line yourself, but Climate Control Company has the trained HVAC technicians with the proper tools needed to complete this task for you. 

How to Conquer A Clogged AC Drain Line On Your Own

The first step is to TURN THE POWER OFF TO THE UNIT. To avoid death or serious injury, this must be STEP ONE. Once the unit is powered off, you can try the remaining steps. I

  1. Take a stiff brush to clear any debris from the end of the line at the outside unit.
  2. Attach the end of a wet/dry shop vacuum suction wand to the outside end of the condensate line & secure it with duct tape. Turn on the vacuum. This may clear the clog.
  3. If the indoor drain pan is full of water, you’ll need to use the shop vac to clean it well, including wiping it with soapy water.
  4. Next, locate the vent tee connecting the drain pan to the pipe. Remove the cap from the top of the line. Use the stiff brush to clear any debris from the tee.
  5. Wearing rubber gloves, carefully pour 1 cup liquid bleach & 1 cup water into the tee & into the line. Let it sit for about 30 minutes. 
  6. If you have someone helping you, have them go outside to check for drainage coming from the pipe. If you’re working alone, place a bucket at the end of the line to check for proper drainage.
  7. Finally, pour more water into the line & check for proper flow. If it is flowing, great! You’ve unclogged the condensate drain.

If after completing the above steps, you still have an AC drain clog, or if after reading you’ve decided, it seems too involved, it’s definitely time to call Climate Control Company: Comfort-Driven, Colorado Style…since 1956.