4 Common Dishwasher Air Gap Problems

An open dishwasher with the loaded racks pulled out.
  • 1-2 hours
  • Intermediate
  • 20-80

The dishwasher air gap is an important part of your machine which helps its normal operation. The air gap allows air in so the dishwasher can drain properly without it creating a vacuum and restricting water from being able to flow out. If this doesn’t work probably, it could mean water will leave the dishwasher at times other than when it’s supposed to. The dishwasher air gap fits onto the top of your sink and should not normally do anything other than allow air into the dishwasher.

1. Water Flowing Out of Dishwasher Air Gap

When the dishwasher is running it's possible for water to flow out of the air gap and onto the countertop. There are a few different reasons for this including a damaged seal, or possibly because of a blockage in the pipe which connects the air gap to the dishwasher. If there is a blockage then this will need to be removed by using a plumber's snake. Check the pipes between the air gap and the dishwasher, and the air gap and the waste disposal. The water flowing out from this air gap might be a very small amount but it can sometimes be more depending on the extent of the problem.

2. Dishwasher Knockout Plug

sink with red countertop in the background

If a new dishwasher or garbage disposal unit has been fitted recently then you must check that the garbage disposal knockout plug is removed. This is essential, otherwise water can come out of the air gap and cause problems for everyone concerned. This should be done at the time of installation; however, it sometimes gets forgotten.

3. Clogged Air Gap

Another common problem is that the air gap itself becomes clogged. This results in many different problems including the dishwasher being unable to drain. If there is no space for air to get into the dishwasher then water won't be able to drain properly.

The air gap can be removed completely and flushed out with water. Plumber's snakes may also be used to clean out any blockages to restore your machine to its normal function.

4. Clogged Vent

If the vent on your dishwasher air gap is clogged then this can cause problems like preventing the dishwasher from draining. The vent can be washed in soapy water to remove any grease and debris causing the blockage.

A clogged or damaged air gap is one of the most common causes of problems people experience with their machine. Dealing with any of these common dishwasher air gap problems will help you to make your dishwasher work much better and more efficiently.