Why Your Dishwasher Isn’t Draining (and the Parts That Can Fix It)

Is your dishwasher leaving a pool of dirty water at the bottom after every cycle? A dishwasher that won’t drain properly is a common problem — and one that’s usually caused by a small, inexpensive part. Before calling a technician, it’s worth checking a few key components that often cause this issue.

Here’s what to look for, how to troubleshoot, and which parts may need replacing.

1. Check the Drain Filter

Your dishwasher’s drain filter traps food particles and debris before they reach the drain pump. If it’s clogged, water won’t be able to drain properly. Remove the bottom rack and unscrew the filter for cleaning. Rinse it under warm water and scrub with a soft brush to remove buildup.

2. Inspect the Drain Hose

The drain hose carries wastewater out of the dishwasher. Kinks, clogs, or improper installation can prevent drainage. Disconnect the hose and check for obstructions. Make sure the hose is elevated properly in a high loop to prevent backflow.

3. Test the Drain Pump

If the pump motor has failed, water won’t drain even when everything else looks fine. You can test the drain pump using a multimeter to check for electrical continuity. A burned-out or jammed pump will need replacement. Reliable Parts carries OEM dishwasher drain pumps designed for your exact model.

4. Examine the Check Valve

The check valve prevents water from flowing back into the dishwasher after draining. If it’s stuck or blocked, it could be the reason water remains in the tub. Cleaning or replacing the valve often resolves this problem.

5. Look at the Air Gap (if installed)

Some dishwashers have an air gap near the sink faucet to prevent backflow. Remove the cap and check for buildup or obstructions inside. A quick rinse and scrub can often restore normal flow.

Pro Tip:

Run your dishwasher on a short cycle with hot water and a cup of white vinegar once a month to help dissolve grease, soap scum, and buildup that can clog filters and hoses.