6 Reasons Why Is My Dishwasher Not Draining


why is my dishwasher not draining

Are you struggling with a dishwasher that won’t drain properly? It’s a frustrating issue that can leave you with dirty dishes and standing water at the bottom of your appliance. But don’t worry; we’ve covered you with six possible reasons why your dishwasher is not draining and how to fix it.

Why Is My Dishwasher Not Draining

To begin troubleshooting a dishwasher that is not draining properly, it is important to determine your drain connection type. To do this, open the cabinet beneath the sink and examine how the corrugated dishwasher drain hose is configured and connected to the sink drain.

The following drain connections are the most common and can help you identify the type of connection you have:

High loop to disposal:

In this configuration, the dishwasher drain hose enters the cabinet from the dishwasher and loops to the top of the cabinet. It is then held in place with tape, a string, or a chain before connecting to the garbage disposal.

High loop to drain:

If your dishwasher is not connected to a garbage disposal, it should still have a high loop. The hose will then connect to the drain pipe before the P-trap on the drain line to prevent sewer gases from entering the dishwasher and causing a foul smell.

Air gap to disposal

Like the high loop to disposal configuration, the hose runs to the top of the cabinet before connecting to the garbage disposal. However, instead of tape or a chain to hold it in place, the hose connects to a fitting at the back of the sink.

If you have an air gap in your dishwasher drain connection, a small cylindrical knob will be installed on the sink’s top to allow air to enter and prevent dirty sink water from draining back into the dishwasher. This air gap acts like an overflow for the dishwasher.

Air gap to drain:

This configuration is the same as the air gap to disposal but without garbage disposal. The hose runs to the air gap and then connects to the drainpipe before the P-trap.

By identifying the type of dishwasher drain connection you have, you can proceed with troubleshooting and determining the cause of your drainage problems.

1. Clogged Drain Hose

A clogged drain hose is one of the most common causes of a dishwasher not draining. Over time, food particles and other debris can get stuck in the hose, preventing water from draining correctly.

Disconnect the hose and remove any blockages with a long, flexible brush or pipe cleaner to fix this issue.

2. Blocked Garbage Disposal

If your dishwasher is connected to a garbage disposal, a blockage in the disposal can cause the dishwasher not to drain properly.

The drain hose from your dishwasher typically empties into the drain of your garbage disposal. If unground food or food sludge has settled in the drainpipe beneath the disposal, it can cause drainage problems even for the best dishwasher.

In many cases, running the garbage disposal is a simple solution that can get your dishwasher draining correctly again.

To prevent clogs and drainage issues, it is a good idea to develop a habit of running the garbage disposal with water for an additional 15 seconds after grinding up food waste.

This will help ensure that all remaining food particles are cleared from the P-trap drain beneath the disposal and prevent future blockages.

This simple step can help keep your dishwasher running smoothly and reduce the need for costly repairs or replacements.

3. Faulty Drain Pump

If your dishwasher’s drain pump is not working correctly, water won’t be able to drain from the appliance. You can test the pump by running a diagnostic cycle or by checking for a humming sound when the dishwasher is supposed to be draining.

If the pump is faulty, it will need to be replaced.

4. Clogged Air Gap

An air gap is a device that prevents dirty water from flowing back into your dishwasher. If the air gap becomes clogged, it can cause the dishwasher not to drain correctly.

Remove the cover from the air gap to fix this issue and clean out any debris inside.

5. Improper Dishwasher Installation

If your dishwasher is not installed correctly, it could be causing drainage issues. Ensure the dishwasher is level and the drain hose is connected correctly.

If unsure, consult the manufacturer’s installation instructions or hire a professional to assess the situation.

6. Malfunctioning Control Panel

In rare cases, a malfunctioning control panel can cause a dishwasher not to drain properly. If none of the other solutions have worked, it may be time to call a professional to diagnose and fix the issue.

Frequently Asked Questions (FAQ)

You’re not alone if you’re having trouble with a dishwasher that won’t drain properly. Here are some frequently asked questions and answers that can help you troubleshoot the issue.

Why is my dishwasher not draining?

There are several reasons why a dishwasher may not be draining properly. It could be due to a clogged drain hose, blocked garbage disposal, a faulty drain pump, a clogged air gap, improper installation, or a malfunctioning control panel.

How can I tell if my dishwasher isn’t draining?

You may notice standing water in the bottom of the dishwasher, a foul odor coming from the appliance, or dishes that aren’t getting cleaned properly. You may also hear a humming noise or notice the dishwasher taking longer than usual to complete a cycle.

What can I do to fix a clogged drain hose?

To fix a clogged drain hose, disconnect it from the dishwasher and use a long, flexible brush or pipe cleaner to clear any blockages. You can also try running hot water through the hose to help loosen any debris.

How can I unblock the garbage disposal?

If your dishwasher is connected to a garbage disposal, a blockage in the disposal can cause drainage issues. To fix this issue, turn off the power to the disposal and remove any visible blockages. Then, run water through the disposal to make sure it’s clear.

What should I do if the drain pump is faulty?

If the drain pump is faulty, it will need to be replaced. You can test the pump by running a diagnostic cycle or checking for a humming sound when the dishwasher is supposed to be draining. It’s best to hire a professional to replace the pump to ensure that it’s done correctly.

How can I clean a clogged air gap?

In most cases, dishwashers with an air gap connection are less likely to experience drainage problems. However, whether your dishwasher has an air gap depends on your local building codes.

Some communities require air gaps, while others only require a high loop in the hose under the sink cabinet. If your dishwasher has an air gap, it will typically be located next to your kitchen faucet.

Sometimes, an air gap can become clogged with debris, preventing your dishwasher from draining correctly and leaving standing water in the tub. To investigate this issue, twist the air gap counterclockwise to remove it and check the inside for any blockages or buildup.

You can clean the air gap with water and a stiff brush, then replace it and rerun the dishwasher cycle. This simple cleaning task can help prevent future drainage problems and ensure your dishwasher continues to run smoothly.

What should I do if my dishwasher was improperly installed?

If you suspect that your dishwasher was improperly installed, it is important to take action to address the issue as soon as possible.

An improperly installed dishwasher can cause many problems, including drainage issues, leaks, and even damage to your kitchen cabinets and flooring.

The first step is to determine whether your dishwasher was improperly installed. Some common signs of poor installation include the dishwasher moving or rocking during use, water leaking from the unit, or the dishwasher door not closing properly.

You may also notice that dishes are not getting cleaned properly or that standing water is in the bottom of the tub after a cycle.

Suppose you suspect that your dishwasher was improperly installed. In that case, it is best to contact a professional installer or licensed plumber to inspect the unit and determine the cause of the problem.

They can assess the installation and identify any issues, such as a loose or incorrectly installed drain hose, a faulty valve, or problems with the dishwasher’s electrical connections.

Reinstalling the dishwasher or making significant repairs may be necessary to correct the issue. While this can be costly, it is essential to address the problem to prevent further damage and ensure that your dishwasher functions appropriately and safely.

What should I do if none of these solutions work?

If you have tried all of the recommended solutions for your dishwasher’s drainage problems and none have worked, it may be time to consider seeking professional assistance.

Using a dishwasher that is not draining properly can lead to a range of issues, including water damage, mold growth, and potential damage to the dishwasher itself.

Your first step should be to consult the owner’s manual for your dishwasher to determine any specific troubleshooting steps you may have missed.

If you still cannot resolve the issue, it may be time to contact a professional repair service or the manufacturer for assistance.

A licensed plumber or repair technician can inspect your dishwasher and identify any underlying issues, such as a faulty motor, valve, or pump.

They may also be able to recommend repairs or replacements to help resolve the issue and get your dishwasher functioning properly once again.

In some cases, it may be more cost-effective to replace an old or damaged dishwasher rather than invest in costly repairs.

Your repair technician can guide the best course of action based on the age and condition of your dishwasher, as well as your budget and needs.

Regular maintenance and proper usage can help prevent many common dishwasher drainage problems.

By keeping your dishwasher clean, using the correct detergent and loading techniques, and promptly addressing any issues, you can help ensure that your dishwasher serves you well for years to come.


Dishwasher drainage problems can be frustrating, but plenty of solutions are available. Begin troubleshooting by checking the dishwasher drain hose, drain valve, and where the dishwasher drain hose connects.

Clogged dishwashers can also be caused by food debris, so be sure to check the dishwasher filter and remove any food particles blocking the drain basket. Also, consider the cleanliness of the spray arm, as buildup can prevent it from properly draining water.

Inspect the sink’s air gap, drain valve bracket, and high loop to prevent water from returning to the dishwasher. If your dishwasher won’t drain properly, try running the rinse cycle, using baking soda and vinegar, or simply running hot water down the drain.

If these solutions don’t work, consider replacing the drain hose, calling a licensed plumber, or replacing the dishwasher altogether. Consult your owner’s manual or online chat feature for more specific instructions or troubleshooting tips.

Additionally, be sure to take advantage of any special offers, product pricing, or services that may be available to you to keep your dishwasher in top shape. With the right tools and tricks, you can rid your dishwasher of any clogs, gunk, or buildup and get it back to properly draining water in no time.

Just remember to always unplug the unit, wear protective gear, and proceed with caution to avoid any accidents or damage to your appliances.

In some cases, the dishwasher may still not properly drain even after trying the aforementioned solutions. This may be a sign of a more serious problem, such as a broken dishwasher motor or faulty valve.

If this occurs, contacting a professional repair service or the manufacturer is recommended for assistance.

It is important to remember that regular maintenance can prevent many common problems with dishwashers. This includes regularly cleaning the dishwasher filter, removing any food debris from the bottom of the tub and inspecting the drain hose.

Also, it is important to use the correct detergent and loading techniques for your specific dishwasher model.

When buying a new dishwasher, select the right type that fits the space in your kitchen and meets your specific needs. There are a variety of brands and models on the market, ranging in color, price, and special features.

Consider your budget and the purpose of your dishwasher, such as energy efficiency or the ability to wash large loads of dishes at once.

In summary, with proper care and maintenance, most dishwashers should be able to properly drain water without any issues.

If a problem does occur, there are many simple solutions and professional services available to help.

Keep in mind the tips and tricks mentioned above to prevent future problems and ensure your dishwasher serves you well for years to come.

Last update on 2024-04-12 / Affiliate links / Images from Amazon Product Advertising API