Reasons Why Your Dishwasher Won’t Drain

Opening your dishwasher to find standing water at the bottom is never a welcome surprise. Whether it happens once or becomes a recurring issue, a dishwasher that won’t drain can disrupt your entire kitchen routine.

Before you assume the worst, here are some of the most common reasons why dishwashers won’t drain – and a few troubleshooting tips you can try at home. These apply to most makes and models across the USA.

1. The Filter is Clogged

One of the most common reasons dishwashers won’t drain is a clogged filter. Over time, food particles, grease, and debris can build up and block water from flowing out. We carry parts for all major brands and models, so if you’re in need of a new filter or any dishwasher replacement parts, we have something that’ll solve your problems.

What to do: Take out the bottom rack and check the filter. If it’s dirty, rinse it well under hot water. If there’s tough buildup, scrub it with a soft brush. Also, try thoroughly rinsing your plates and cutlery before putting them in the dishwasher to reduce the amount of food particles getting into the filter.

2. A Blocked or Kinked Drain Hose

The drain hose carries water out of your dishwasher and into your sink drain or garbage disposal. If it’s clogged or bent out of shape, water can’t pass through.

Just a tiny kink can slow down or completely stop drainage, so it’s worth it to take a careful look.

What to do: Inspect the hose for any obvious kinks or blockages. If you’re comfortable doing so, disconnect the hose and flush it out to clear any debris. Make sure you turn off the unit’s power and water supply first.

3. Garbage Disposal Troubles

Many dishwashers in U.S. homes are connected to the kitchen’s garbage disposal. If that’s the case, a clog in the disposal or a newly installed unit with the dishwasher knockout plug still in place can cause drainage issues.

This is one of the quickest fixes if caught early, however, it often gets overlooked during installation. Take the time to make sure you garbage disposal is working as it should.

What to do: Run your garbage disposal to clear any blockages. If it’s a new installation, check that the knockout plug has been removed.

4. Clogged Air Gap (If You Have One)

Some kitchen sinks are fitted with an air gap – usually a small metal or plastic cylinder next to the faucet. Its job is to prevent dirty water from backing into the dishwasher. If it’s clogged, it can stop the dishwasher from draining.

A clogged air gap  may not seem like a huge deal, but in some setups, it can cause your drainage to fully stop.

What to do: Remove the cap and check for any visible gunk or buildup. Clean it out and test your dishwasher again.

5. Drain Pump Problems

If nothing above seems to be the issue, your dishwasher’s drain pump might be to blame. The pump’s job is to push water out during the drain cycle, and if it fails, water will remain in the bottom of your unit.

Similar to the filter, and many motorized parts, the drain pump can wear out over time or get jammed by debris.

What to do: If you hear a humming noise when the dishwasher is trying to drain, it’s a sign of pump failure. At this point, it may be best to call in a repair professional.

6. Look for Error Codes

Many newer dishwasher models come with diagnostic features or display error codes when something’s wrong. Look up your model’s manual or check the manufacturer’s website to see what the code means and whether it points to a drainage issue. Because these codes point directly to the problem, they can save you time.

When to Call in an Expert

If you’ve gone through these steps and still don’t know why your dishwasher won’t drain, it may be time for a professional repair. Whether it’s a faulty electrical connection or a worn-out part, a skilled technician can have your dishwasher running smoothly again in no time.

Remember, we offer shipping across the USA, so reach out to the team at Max Appliance Parts today to help you find the right fix – we’re always happy to help.