How to Troubleshoot a Dishwasher That Won’t Drain

28-Feb-2025

Water all over your kitchen from a dishwasher that won’t drain? No need to panic and go back to washing dishes by hand. Before you call us to come and fix your dishwasher, here are the common causes of a clogged dishwasher that won’t drain and how to troubleshoot them.

1. Check for a Clogged Filter

Food particles and debris often collect at the bottom of your dishwasher, causing water to pool around the filter.

• Locate the Filter: Open the bottom panel of your dishwasher. You will typically find the filter where the largest amount of water collects.
• Action: Remove the filter and rinse it thoroughly with hot water. Carefully inspect the drain area beneath it for any large debris or objects that may be obstructing the flow of water.

2. Inspect the Drain Hose

A kinked or clogged drain hose can prevent your dishwasher from draining properly.

• Action: Unplug your dishwasher. Follow the drain hose to where it attaches to your sink’s drain. Inspect the hose for any visible kinks. Check for clogs by running hot water through the hose to loosen any debris that may have become trapped inside.

3. Examine the Garbage Disposal Connection

If your dishwasher is hooked up to drain via your kitchen sink, a clog in the garbage disposal can cause drainage issues.

• Action: Run your disposal to clear out any food waste.
• Important Note: If you have recently had a new disposal installed, ensure that the knockout plug was removed. Many people make this common installation mistake.

4. Look at the Drain Pump

The drain pump is the core of your dishwasher’s drainage system. It is responsible for forcing water out of the unit during the drain cycle.

• Action: Listen closely during the drain portion of the cycle. A failing drain pump may emit a grinding or buzzing sound. Note that this pump can get jammed by small items like broken glass or plastic package tabs.

5. Check the Air Gap (If Applicable)

An air gap is designed to prevent dirty sink water from backflowing into your dishwasher, but it can get clogged over time.

• Action: Unscrew the decorative cap covering the air gap. Clear out any debris that has accumulated inside. The air gap should be checked periodically to ensure proper drainage.

Still Stuck? We Can Help!

If none of these steps work, it is time to call in the professionals.

Avantgarde Appliance Repair has been Ottawa’s dishwasher repair specialist for over 35 years. We utilize the latest diagnostic tools and have the experience to provide the most cost-effective solution, whether the issue is a malfunctioning pump, an electrical problem, or a deep-seated clog.

📞 Call us today at (613) 869-0101

🌐 Schedule your repair online today!