5 Minute Fix for a Dishwasher That Won’t Drain

Updated: Apr. 19, 2024

Learn how to keep your dishwasher drain line from clogging, and what to do if it does.

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Time

A few minutes

Complexity

Beginner

Cost

Free

Introduction

If your dishwasher won't drain, you can probably fix it yourself. Here are the steps to get your dishwasher working again — fast!

Tools Required

  • Bucket
  • Flathead screwdriver
  • Wire coat hanger

A dishwasher that won’t drain is a common problem and one of the easiest appliance repairs. I enjoy fixing dishwashers that won’t drain because it’s so quick and gratifying. You can do the entire repair in less than five minutes.

Almost always, there’s food debris caught somewhere in the drain tube. That brings us to the age-old question, “Should I rinse my dishes before loading them in the dishwasher?” Here’s my advice: Scrape off the chunky stuff but leave on the sauce! Some food residue on the dishes acts as a catalyst to activate your detergent’s cleaning action. If your dishes are still wet after a wash cycle, here is a simple trick to help you  dry wet dishes in no time!

Now, back to the issue at hand. Symptoms of a clogged dishwasher include:

  • Water above the filter at end of cycle;
  • Blinking LED lights;
  • Low humming sound from base of dishwasher;
  • Error code displayed;
  • Dishwasher cycle won’t start. (Dishwashers always drain for a few minutes at the start before filling with water.)
  • Cycle won’t finish.

Project step-by-step (4)

Step 1

Activate the Drain/Cancel Feature

  • Try to reset the dishwasher. This also activates the drain mechanism.
  • Press the cancel button for three full seconds.

Or:

  • Press the start button for three full seconds.

Or:

  • Press two buttons at the same time, indicated by small text (see photo).

This will get the drain motor spinning and might be all you need to start your dishwasher draining again.

Activate Cancel FeatureScott Flint for Family Handyman

Step 2

Check and Clean Drain Tube Air-Gap

If those suggestions didn’t make your dishwasher drain, then something is caught in the drain tube. If your dishwasher has an air-gap in its drain tube, that’s where you’ll find the clog. The air-gap is a round R2-D2-looking thing up near the kitchen faucet.

Here’s how to check it and clean it:

  • Pull straight up on the silver air-gap cover.
  • Remove the air-gap cap by unscrewing it if it’s round, or by gently prying the two plastic tabs holding on the cap with a flat-head screwdriver as you lift it off.
  • Check the small round center tube for food debris. Remove by pinching it with your fingers.
  • Press the drain or reset button and close the dishwasher door. A three-inch column of water should shoot out of that small central tube.
  • Put the cap back on.

If you see a big column of water when you press the drain or reset button, the problem is fixed. If not, move on to Step 3.

Check And Clear Drain GapScott Flint for Family Handyman

Step 3

Clear Tube Before Air-Gap

  • Push a straightened wire coat hanger 10 inches into the small air-gap tube.
  • Set the dishwasher to drain/cancel/reset and close the door to start draining as you move the coat hanger up and down to break up the obstruction.
  • Look for a column of water shooting up three inches above small air-gap tube.

If you don’t have an air-gap up by the kitchen sink, your dishwasher drain hose goes directly into your garbage disposal or your kitchen sink drain. If this is the case, proceed to Step 4.

Clear TubeScott Flint for Family Handyman

Step 4

Clear Drain Tube Under Sink

  • Loosen the hose clamp on your drain tube where it connects to your garbage disposal or kitchen sink drain. Do this by turning it counter-clockwise with flat-head screwdriver.
  • Put the drain hose in a bucket and set your dishwasher to drain by pressing the drain/cancel/start button for three seconds. Then close the dishwasher door to start it.
  • While the drain tube is in the bucket, shake it to loosen the obstruction.
  • When water comes shooting out, let it continue until it’s fully drained. If the bucket fills up, open the dishwasher door to stop the drain.
  • Wiggle the drain hose back onto the garbage disposal unit or kitchen sink drain and tighten the hose clamp.

Pro tip: If you just installed a new garbage disposal before the dishwasher drain problem occurred, the cause may be a plastic plug inside the tube that connects to the dishwasher drain. To remove this plug, put your flat-head screwdriver in the disposal’s drain tube pipe and hit the back of the screwdriver with a hammer. That will knock out the plastic plug.

Clear Drain Tub Under SinkScott Flint for Family Handyman