How to Connect an AC Condensate Drain to a Sink

AC condensate drains allow the moisture that is removed from your house during the process of cooling to drain out of the machine.

Many people assume that they can attach an AC condensate drain to a sink or sewer line to dispose of the drainage. But this violates most building codes because the AC will also produce a jelly-like substance that can plug up sewer pipes. Attaching the drain to sinks will also create an air trap that will give rise to constant gurgling and burping from the sink. It's best to drain your AC condensate onto soil. .

Purchase several types of PVC pipe connectors. You will need one that will screw onto the condensate drain on your AC. You will also need a connector for every bend the pipe will take on its way to the drain.

Lay your PVC pipe along the path it will take to your drain spot. Your drain spot is simply any location where the pipe may drain onto soil, which is allowed by most building codes.

Mark where you need to cut the pipe to fit into the connectors and make what bends are needed in the line. Remember to allow for at least an 1 inch of the pipe to extend into the connector.

Begin to connect your pipe, starting at the condensate drain. Coat the threads of the connector with PVC adhesive and then screw the first pipe on. Go to the next connection and coat the outside of the pipe (that will go into the connector) and the inside of the conenction. Fit the two together. Do this until you have connected your entire pipeline.

Raise your drain pipe up onto adjustable pipe stands. Turn the bases counter-clockwise to decrease the height of the stand and clockwise to increase it. You want your pipe to slope sown 1/4 inch per foot all the way to the ground level where it will drain.

Things You Will Need

  • Pipe connectors
  • PVC pipe
  • PVC saw
  • PVC adhesive
  • Adjustable pipe stands
  • Air compressor


  • AC condensate drains can produce a jelly-like substance containing debris filtered from the interior air. This jelly will build up and block the pipe. Once a year you should disconnect the pipe at the AC unit and blow compressed air through the whole pipeline to clear it. If there is a lot of jelly build-up, you may have to break apart the connections, clear out each section of pipe, then reconnect the sections.


  • Although it may seem easier and more convenient to connect to a sink or sewer pipe, do not do this. You could face heavy fines if caught violating building codes in a damaging way.

About the Author

Cassandra Tribe has worked in the construction field for over 17 years and has experience in a variety of mechanical, scientific, automotive and mathematical forms. She has been writing and editing for over 10 years. Her areas of interest include culture and society, automotive, computers, business, the Internet, science and structural engineering and implementation.