How To Fix Washing Machine Drain Overflows

Water that pools around your washing machine can be caused by several issues that lead to structural damage within your home. In this guide, we detail steps that you can take to identify and fix this problem.

Written by Dana Getz + 1 other Reviewed by Jacquelyn Kfoury Updated 06/17/2024

If your washing machine drain overflows, the problem could be as simple as a clogged drainpipe or as serious as a main sewer line blockage. Addressing the issue as soon as possible may prevent lasting damage to your home. We’ll show you how to diagnose the problem, provide instructions for a do-it-yourself (DIY) fix, and let you know when it’s time to call in the experts.

How a Washing Machine Drains

At the end of a cycle, your washing machine removes water from its tub using a pump that forces water into a washing machine drain hose. This hose curves up and out of the machine to meet the standpipe, which is typically located near your hot and cold water supply valves. If your washer and its parts work as they should, water moves through the hose and into the standpipe, where it’s eventually carried to your home’s main sewage line.

When any part of the process malfunctions, the washing machine’s drainage system may overflow, requiring swift action to identify and fix the issue.

In the video below, Ask This Old House plumbing and heating expert Richard Trethewey explains how to install an automatic shutoff valve for your washing machine supply hoses.

How To Diagnose an Issue With Your Drain

First, you’ll need to confirm that your washer’s drain line is the issue. Some advanced washing machines have signal errors to identify the cause of a leak, but you’ll need to run your own diagnostic test with most models.

Start by running your washer through a drain cycle. Observe the washing machine as it pumps water into the hoses and up into the standpipe. If you see water back up and out of the standpipe, your washer’s drain is most likely the issue.

The amount of time it takes for the standpipe to fill up and overflow helps you diagnose where the clog is located. Here’s what each time frame might mean:

A few seconds: If the pipe fills up and overflows within seconds, the clog is most likely located near the standpipe’s surface or in a washing machine hose. If the clog is small, you may be able to clear it with a hand-operated snake.
30 seconds to a minute: If the stoppage doesn’t cause the water to surface for 30 seconds or more, the clog may be deeper in the drainpipe system. This may require a long drain snake to reach deep into the pipe and free the clog. If you can’t reach the clog with your snake, contact a plumber to assess the proper course of action.
More than a minute: Water that takes more than a minute to overflow after entering the drainage pipe may indicate a more severe blockage deeper within the plumbing system. Contact a licensed plumber to inspect your home’s sewage lines and identify the issue.

Be prepared to stop the washing machine cycle once you spot a leak. Clogs aren’t always the culprit when it comes to an overflowing drainpipe. Inadequately sized drainpipes and kinked hoses can also cause an overflow. To be sure of the issue, contact a reputable plumber like ARS Rescue Rooter to diagnose it.

How To Operate a Drain Snake

Many soft-debris clogs that reside in a washing machine hose, standpipe, or plumbing system can be cleared with a drain auger, also known as a drain snake. If you don’t have one, they can usually be rented from your local hardware store. Some electrically powered, hand-operated drain snakes are less likely to damage your plumbing. To operate a snake, follow these steps:

Push the tip of the cable into the drain opening and turn the handle on the drum to release it into the pipe. You may need to loosen a thumbscrew on the drum to allow the cable to unspool.
Keep pushing the head of the snake deeper into the pipe until you feel resistance.
Tighten the thumbscrew, then rotate the snake clockwise or counterclockwise until you feel the clog break free.
Loosen the thumbscrew once again, then pull the snake out of the drain.
Repeat a drain cycle to ensure the pipe is clear and can drain.

If the drain snake meets resistance but these steps don’t work, the clog may be made of material that’s too hard for the tip of the cable to snag, such as a tree root. In this case, you’ll need to call a plumber. Another culprit could be your city’s sewage system being improperly maintained, resulting in your main line backing up.

How To Prevent Your Drain From Overflowing

To reduce the likelihood of a washing machine drain overflow, clean and inspect your washer and its parts regularly.

Use a garment bag or lint bag when appropriate to prevent the excess buildup of lint inside the drainpipes.
If it’s accessible, inspect and clean your washer’s lint trap or filter.
Ensure there’s at least 1/2 inch between the drainpipe and discharge hose to promote proper drainage.
Use the correct detergent to prevent the buildup of soap residue.
Clean your washing machine hoses and drainpipe regularly.

Repairing or Replacing Your Washing Machine

Like all major systems and appliances, your washing machine is likely to endure normal wear and tear over time. So if drainage issues persist you may need to replace the machine and install a new washer. To cover repair costs due to your washing machine or another appliance breaking down in normal use, we recommend that homeowners consider a home warranty.

Typically, home warranty plans cost $54–$61 per month. Whenever a covered system or appliance breaks down due to normal wear and tear, homeowners with a home warranty plan only have to pay a service fee—usually in the range of $65 to $125—to have the item repaired or replaced. This can save a lot of money in the long run, particularly for older homes or expensive appliances like a washing machine.

Our Conclusion

When your washing machine drain overflows, quick action may prevent damage to your home. If you can’t DIY the problem, we recommend calling a local plumber. As always, it’s worth calling around to get cost estimates before hiring an expert.

FAQ About Fixing Washing Machine Drain Overflows

Why does my washing machine keep draining?

If your washing machine drains while filling, check that the washer’s drain hose isn’t placed too far into the standpipe, as there needs to be an air gap to prevent premature draining. Additionally, ensure that the bend in your drain hose is above the height of the washing machine. Once the hose is in the proper position, use zip ties to secure it in place.

What causes a washing machine drain to overflow?

The most common reason for overflowing is a blockage in the drain hose or standpipe. Kinked hoses and wrong-sized pipes can also cause overflows.

Can I put Drano down my washing machine drain?

Yes, Drano or any drain cleaner can be used to unclog your washing machine drain. However, don’t put the Drano in the washing machine itself, and make sure you run the washer without a load of laundry before normal use.

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