Dishwasher Troubleshooting

Common Dishwasher Problem

Dishwasher Not Draining

Is your dishwasher not draining? This guide covers common causes, DIY troubleshooting steps, and when to call a professional repair service.

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Why Is My Dishwasher Not Draining?

When your dishwasher experiences not draining, it can be frustrating and disruptive. Understanding the potential causes can help you determine whether you need professional repair.

Common Causes of Dishwasher Not Draining

Clogged Drain Filter

Food debris accumulating in the drain filter is the most common cause of drainage problems.

Blocked Drain Hose

The hose connecting the dishwasher to your plumbing can kink or clog.

Garbage Disposal Knockout Plug

New disposals have a knockout plug where the dishwasher connects. If not removed during installation, water can't drain.

Clogged Air Gap

If your setup includes an air gap, debris inside prevents proper drainage.

Drain Pump Failure

The pump that expels water can fail, leaving standing water after cycles.

Usually requires professional repair

Check Valve Stuck

The check valve prevents backflow. If stuck closed, water can't drain out.

Diagnostic Steps

Check Filter/Trap

Remove and inspect the filter at the bottom of the dishwasher for debris.

Run Garbage Disposal

Run the disposal to clear any blockage at the connection point.

Inspect Drain Hose

Check for kinks in the hose under the sink. Ensure it's not pushed too far into the disposal or drain.

Warning: Have towels ready - water may be in the hose.

Check Air Gap

If you have an air gap (chrome cylinder on sink), remove the cap and clean any debris inside.

Listen for Drain Pump

During the drain cycle, you should hear the pump running. No sound may indicate pump failure.

DIY Fixes You Can Try

Clean Drain Filter

easy

Remove and thoroughly clean the filter and any accessible drain components.

Tools needed: Soft brush

Clear Drain Hose

moderate

Disconnect the hose and flush with water to clear blockages. Check for kinks and straighten.

Tools needed: Bucket, Towels

Remove Knockout Plug

moderate

If recently installed disposal, use a hammer and screwdriver to knock out the plug inside the disposal inlet.

Tools needed: Hammer, Screwdriver, Needle-nose pliers

Clean Air Gap

easy

Remove the cap and use a brush to clear debris. Flush with water.

Tools needed: Small brush

When to Call a Professional

Contact Sub-Zero Repair Weston if:

Drain pump is not running or making grinding sounds
Water continues to back up after clearing blockages
You cannot access or remove the drain hose
The dishwasher is built-in with limited access

Prevention Tips

Clean the filter regularly
Scrape food from dishes before loading
Run the disposal before starting dishwasher
Don't put grease down the drain

Professional Repair Service

Sub-Zero Repair Weston provides transparent, upfront pricing after a thorough diagnostic evaluation. Our service call fee is applied toward the repair cost when you choose to proceed.

Diagnosis

Thorough Evaluation

Warranty

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