Help! My Dishwasher Won't Drain

Finding a pool of standing water in your dishwasher after running a cycle is never a good thing. Normally, the water drains before you ever open the door. You're probably scratching your head and wondering, "Why won't my dishwasher drain?" Don't throw in the towel and start washing dishes by hand just yet.

Want to know what's wrong with your dishwasher? Keep reading to find out.

The Four Most Common Reasons Your Dishwasher Won't Drain

The dishwasher is one of the best appliances ever invented. But if it stops draining, you could end up with a sink full of dirty dishes or, even worse, a flooded kitchen floor. Here's what could be wrong with your dishwasher:

  1. Clogged drain hose: The drain hose removes all the water from the dishwasher.
  2. Dirty filter basket: Every dishwasher has a filter basket that covers the drain. It’s designed to prevent large debris from blocking the drain, but this same debris can clog the basket (and the drain).
  3. Broken drain valve: The drain valve opens at the end of the washing cycle, but if it malfunctions, the dishwasher will stay full of water.
  4. Blocked air gap: An air gap is a device that prevents dirty water from backing up into the dishwasher. If it gets clogged, your dishwasher won't drain properly.

It takes a bit of trial and error to determine which of these reasons is the culprit. And the problem may even not be what you expected.

Here's how to troubleshoot your dishwasher full of standing water:

  • Is the problem with the plumbing system or the dishwasher itself? Clean the filter and basket. If the dishwasher drains when you finish, crisis averted!
  • Do other drains in the house still work? Sometimes house-wide plumbing issues such as a blocked main sewer line can cause a non-draining dishwasher. Do your bathtubs, showers, and sinks drain without any problems? If so, then you know the problem is with the dishwasher.
  • Does your dishwasher have power? Your dishwasher won't be able to empty without a working power source. Make sure the outlet has power and check the breaker box for tripped circuits.

How to Fix a Dishwasher That Isn't Draining

After you troubleshoot the problem, it's time to take action. Start with the easiest fix and move on from there. Try these four simple tips to fix your dishwasher:

  1. Run the garbage disposal. The drain hose empties into the garbage disposal drain. If there is food stuck in the disposal, your dishwasher may not empty fully. Clearing the disposal may fix the problem.
  2. Remove blockages. A clog anywhere in your dishwasher will prevent it from draining. Pull out the filter basket and make sure it's not full of food particles. Check the air gap for blockages. Wipe the interior and clean the filter to remove any missed debris.
  3. Look over the drain hose. Make sure it’s in good condition. It should be free of kinks and have a tight seal. Use a wire hanger to remove or loosen clogs.
  4. Clean the drain valve. It’s usually located under the dishwasher and can be accessed by removing the kick plate. Press on the gate arm gently to see if it’s stuck. If the gate arm won’t move, the solenoid will probably have to be replaced.

After completing each step, rerun the dishwasher to see if it drains.

Clear Clogged Drains Fast with Mr. Rooter

If your dishwasher remains full of water, it's time to reach out to a professional plumbing service. You can count on your local Mr. Rooter® Plumbing to lend a hand. Connect with us online or call to schedule expert dishwasher repair.