How to Clean the Air Gap in a Dishwasher

An air gap provides a way for air to remain on top of the water in a dishwasher drain line. The air pressure keeps the water from draining out of the dishwasher until the water pump engages in the cycle to push the water out to the drain line. Air gaps require cleaning when dirty or clean water is standing in the bottom of a dishwasher at the end of a cycle. A sink drain or garbage disposal that works ineffectively to cause clogs results in an air gap stopping up. This is also evident in a dishwasher draining into a sink.

Dishwasher air gaps promote good drainage so the silverware and dishes are clean.
  1. Locate the air gap on the top of the kitchen sink. It is a cylindrical metal device that installs next to the faucet handles and is about 4 inches tall.

  2. Open the kitchen cabinet under the sink and note that the Y connector attaches to the bottom of the air gap. Remove the connector by turning the small screw in the metal band that secures it to the air gap. Turn the screw with a small flat screwdriver counterclockwise to loosen the band. Pull the Y connector off the air gap.

  3. Remove the Y connector from the dishwasher drain line following the same procedure. Remove the opposite end of the Y connector from the garbage disposal by turning the plastic nut that attaches it counterclockwise until the Y pulls off.

  4. Take the Y outside and clean all three entrances with the garden hose. Use a hose nozzle to add extra water pressure to force any clogs or foreign materials out of the Y. The water will run clear out of each entrance and in a full circle upon exiting the entrances when the clog is clear.

  5. Check the opening on the garbage disposal where the Y connects. Make sure that there are no large items covering the opening that will stop up the dishwasher drainage.

  6. Replace the Y onto the garbage disposal, dishwasher drain line and the air gap. Turn the screws on the air gap and dishwasher connections clockwise to tighten the metal bands. Turn the plastic nut on the disposal side clockwise to tighten.


  • Make sure that the dishwasher is not running and the garbage disposal is off when cleaning the air gap.

About the Author

Mary Lougee has been writing for over 10 years. She holds a Bachelor's Degree with a major in Management and a double minor in accounting and computer science. She loves writing about careers for busy families as well as family oriented planning, meals and activities for all ages.