Why Does My Dishwasher Not Drain?

If your dishwasher is not draining, the problem is usually caused by a clogged filter, blocked drain hose, garbage disposal issue, or a failing drain pump.

When water remains at the bottom of the dishwasher after a cycle, it means something is preventing proper drainage.

Here’s what to check.

1) Clogged Dishwasher Filter

Most modern dishwashers have a removable filter at the bottom of the tub.

Food particles, grease, and debris can build up over time and restrict water flow.

What to do:

• Remove the bottom rack
• Locate and unscrew the filter
• Rinse it thoroughly under warm water
• Remove any trapped debris

Reinstall the filter and run a short cycle to test.

A clogged filter can also cause odor problems if debris sits inside the machine.

If your dishwasher smells even after cleaning, trapped food particles are often the cause.

2) Blocked Drain Hose

The drain hose carries wastewater from the dishwasher to the sink drain or garbage disposal.

If the hose is kinked or clogged, water cannot exit properly.

Check for:

• Kinks behind the dishwasher
• Blockages in the hose
• Improper installation height

Straighten or clear the hose if necessary.

3) Garbage Disposal Connection Issue

If your dishwasher drains through a garbage disposal, a blockage there can prevent proper drainage.

If the disposal was recently installed, the knockout plug inside the disposal inlet may not have been removed.

Run the garbage disposal and check for clogs.

4) Drain Pump Failure

If you hear humming but the water does not drain, the drain pump may be faulty.

Signs include:

• Standing water after every cycle
• Unusual grinding noises
• Dishwasher stopping before completing drain

A failing pump may need replacement.

5) Air Gap Blockage (If Installed)

Some sinks have an air gap mounted near the faucet.

If this becomes clogged, water can back up into the dishwasher.

Remove the air gap cover and clean any debris inside.

When to Call a Technician

Call for service if:

• The dishwasher repeatedly fails to drain
• You notice electrical burning smells
• The pump makes loud grinding noises
• Water leaks under the unit

Persistent drainage problems may require professional repair.

Quick Recap

If your dishwasher is not draining, check:

• The filter
• The drain hose
• Garbage disposal connection
• Drain pump
• Air gap

Most drainage issues are caused by simple clogs and can be resolved without replacing the appliance.