5 Reasons Your Whirlpool Dishwasher Isn’t Draining

What’s more frustrating than opening your Whirlpool dishwasher after a cycle and finding a pool of dirty water at the bottom? A dishwasher that won’t drain properly can’t clean your dishes effectively, and standing water can cause unpleasant odors, bacterial growth, and even damage your appliance.

Drainage problems usually come from a few common issues, many of which are relatively easy to diagnose and fix at home without calling a professional. In this guide, we’ll cover five of the most common reasons your Whirlpool dishwasher might not be draining, and some practical steps you can take to resolve each problem.

1. Clogged Filter or Food Trap

The most common cause of dishwasher drainage problems is a clogged filter or food trap.

Whirlpool dishwashers use a filtration system at the bottom of the tub to catch food particles, grease, broken glass, and debris before they reach the drain pump. When this filter becomes overly clogged, water can’t flow through it properly and remains trapped inside the dishwasher.

Common culprits include:

• Food scraps and grease
• Paper labels from jars
• Fruit pits, seeds, and small bones
• Soap residue buildup

Many homeowners don’t realize their dishwasher has a removable filter that requires regular cleaning.

How to fix it:

1. Remove the bottom dish rack.
2. Locate the cylindrical filter assembly at the bottom of the tub (usually centered or toward the back).
3. Turn the upper filter counterclockwise and lift it out.
4. Remove the lower filter basket.
5. Rinse both parts under warm running water.
6. Use a soft brush or toothbrush to scrub away grease and debris, especially from the fine mesh screen.
7. Check the filter housing area for loose debris and remove it.
8. Reinstall the filters securely and lock them into place.

Run a short rinse cycle to see if the dishwasher drains properly.

Prevention tip: Clean the filter at least once a month, or more often if you run frequent loads or don’t pre-scrape dishes.

2. Blocked or Kinked Drain Hose

The drain hose carries wastewater from your dishwasher to either your garbage disposal or your home’s drain line. If this hose is kinked, twisted, pinched, or clogged, water won’t be able to exit the dishwasher properly.

This issue often occurs after:

• Dishwasher installation
• Kitchen renovations
• Moving or replacing appliances

How to fix it:

1. Turn off the power and water to the dishwasher.
2. Remove the mounting screws and carefully pull the dishwasher out from under the counter.
3. Locate the drain hose running from the dishwasher to the sink drain or garbage disposal.
4. Inspect the entire length for sharp bends, kinks, or pinched areas.
5. Ensure the hose has a proper high loop under the countertop. The hose should rise as high as possible before dropping down to the drain connection.
6. Straighten or reposition the hose as needed and secure it with zip ties or clips.

If you suspect an internal clog:

• Disconnect the hose from both ends.
• Run water through it using a faucet or garden hose.
• If water doesn’t flow freely or the hose looks damaged, replace it.

3. Clogged Garbage Disposal or Drain Connection

If your Whirlpool dishwasher drains into a garbage disposal, a clog or installation issue in the disposal can prevent proper drainage.

Common issues include:

• A clogged garbage disposal
• A blocked sink drain
• A knockout plug is still installed in the disposal’s dishwasher inlet

New garbage disposals come with a plastic knockout plug covering the dishwasher connection port. If this plug wasn’t removed during installation, the dishwasher will never drain.

How to fix it:

1. Disconnect the dishwasher drain hose from the garbage disposal inlet.
2. Shine a flashlight into the inlet port.
3. If you see a solid plastic plug, it must be removed.
4. Insert a screwdriver into the disposal from above, position it against the plug from the inside, and tap it gently with a hammer until the plug falls out.
5. Retrieve the plug from inside the disposal before running it.

Even if the plug is removed, the disposal itself may be clogged. Run it with cold water for 30 seconds to clear food debris.

For dishwashers connected directly to the sink drain, check the drain trap and line under the sink for grease or food buildup. Cleaning the trap or using a plumber’s snake may resolve the issue.

4. Faulty Drain Pump

The drain pump actively pushes water out of the dishwasher. If the pump fails, water will remain in the tub even if everything else is clear.

Signs of a drain pump problem:

• No draining sound during the drain cycle
• A humming noise, but no water movement
• Standing water despite clean filters and hoses

How to diagnose:

1. Disconnect power to the dishwasher.
2. Remove the lower access panel or tip the dishwasher back.
3. Locate the drain pump at the bottom of the unit.
4. Check the pump impeller for debris like glass shards, toothpicks, or labels.
5. Spin the impeller manually; it should move freely.

If the pump isn’t jammed, test it with a multimeter. Most Whirlpool drain pumps measure roughly 50-150 ohms, depending on the model. No continuity or infinite resistance indicates a failed pump.

Drain pump replacement is a manageable DIY repair for experienced homeowners, but it requires careful installation to prevent leaks.

5. Clogged or Faulty Drain Valve (Select Models)

Some Whirlpool dishwasher models use a drain valve or drain solenoid that opens to allow water into the drain pump. If this valve sticks closed, water won’t drain even if the pump is working.

Causes include:

• Mineral deposits from hard water
• Debris buildup
• Electrical solenoid failure

How to fix it:

1. Unplug the dishwasher.
2. Access the drain valve near the pump.
3. Inspect it for debris or visible damage.
4. Clean mineral buildup using white vinegar.
5. Test the solenoid with a multimeter during the drain cycle.

If the solenoid receives power but doesn’t activate, the valve assembly must be replaced.

How to Prevent Future Draining Issues

Once your dishwasher is draining properly again, simple maintenance can prevent future problems:

• Scrape large food particles from dishes
• Clean the filter monthly
• Run hot water at the sink before starting a cycle
• Use rinse aid to reduce mineral buildup
• Run an empty cycle with white vinegar periodically

These habits help prevent grease, debris, and mineral deposits from interfering with drainage.

The Bottom Line

A Whirlpool dishwasher that isn’t draining is usually caused by common issues you can fix at home. Regularly cleaning the filter, checking hoses, and maintaining the drain connection can prevent most problems from recurring.

If these steps don’t work, the issue may be with the drain pump or valve. In that case, call a professional to ensure your dishwasher is repaired correctly.