By reading the following DIY project you consent to the terms in the DIY disclaimer.

How to Clean a Clogged AC Condensate Drain Line

Water pooling around your furnace/AC unit in the house most likely indicates a clogged condensate drain line. This PVC pipe connects to the drain pan inside the equipment. When you run the heat or AC, moisture drips into the pan and trickles through the PVC pipe to a drain. Mold and bacteria can grow in this moist environment and form gunk that blocks drainage. If you do not follow the steps for how to clean a clogged AC condensate drain line, water will keep pooling inside. A musty smell will develop, and mold could infiltrate your home’s structure.

Tools NeededClean AC Condensate Drain Line

  • Narrow brush on long flexible wire
  • Wet/dry shop vac
  • Funnel
  • Bucket
  • Measuring cup

How to Clean a Clogged AC Condensate Drain Line Directions

  1. Turn off the thermostat.
  2. Turn off the circuit supplying electricity to the air conditioning system.
  3. Locate the condensate drain line. Due to the freezing climate in Pennsylvania and New Jersey, the condensate line will be inside. It comes out of the furnace/air conditioner equipment in your utility room or basement. It is PVC piping that will route toward a floor drain or use a pump connected to the washer’s drainpipe.
  4. The condensate line near the equipment will have a T-shaped vent with a screw cap.
  5. Unscrew the cap and slide the narrow brush toward the downward curving drain trap. This is probably where the sludge has built up.
  6. Push and pull on the brush to dislodge gunk.
  7. Find the end of the PVC drain line.
  8. Wrap a rag around the pipe so that you can fit the hose of the wet/dry vac over it. The connection does not have to be tight but adequate enough to enable suction.
  9. Screw the cap back onto the T vent.
  10. Turn on the wet/dry vac and let it run for 1 or 2 minutes.
  11. Check inside the vac to see how much water was pulled out.
  12. Disconnect the vacuum hose.
  13. Unscrew the T vent’s cap again and insert a funnel.
  14. Fill a bucket with clean water and pour water into the funnel.
  15. Confirm that water is flowing through the pipe to the other end.
  16. Put the T vent cap back on.
  17. To prevent mold and bacteria growth in the future, pour 1/4 cup distilled white vinegar into the line at the T vent once a month.

If this procedure does not clear the line, the blockage is between the T vent and the drain pan. The AC unit needs to be opened and the pan inspected. The PVC pipe may need to be cut open and a longer brush pushed through the pipe. An AC repair technician from Oliver has the tools to resolve any blockage. We can also open and close the PVC piping as necessary.

Seasonal Maintenance Prevents Condensate Drain Blockages

The workings of the drain line are largely invisible until you step into a pool of water. You can avoid this problem and others with a seasonal AC tune-up. Because this can be easy to forget, Oliver offers maintenance plans that keep you on track. We’ll ensure the condensate drain line is clear and confirm that all mechanical parts are ready for summer cooling. Don’t risk moisture damage to your home. Contact Oliver today.

Need help with this project?

If you do not have the time, tools, or experience necessary to complete the project, please contact the professionals at Oliver for help.

Contact us today at 1-888-810-2681 Get a Free Estimate