Washing Machine Water Backing Up Into Bathtub? (Here's What You Can Do)

Benjamin Wright
by Benjamin Wright

Watching dirty washing machine water back up into your bathtub can be a confounding experience for some. It can be difficult to pinpoint the source of the problem if you are not experienced with drainage systems. As a result, it is common for people to think that the problem is more serious than it really is.

Check the drainage system for your washer if water is backing up into your bathtub when you run it. Snake the drain to remove any clogs. If this doesn’t work, you can install a non-return valve or replace any damaged or outdated pipes to fix the problem and avoid problems in the future.

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Why Does Water Backflow Occur?

In most cases, a shared drainage pipe causes water from your washing machine to back up into your bathtub. In perfect condition, it can be perfectly fine for a washing machine and bathtub to share a drainage pipe. However, when the drain is clogged, there is nowhere for the water to go but back.

Since the drain in the bathtub is the path of least of resistance, the wastewater finds its way into the bathtub. The answer to the problem is, therefore, to clear out the drainage pipe to make it easier for the washing machine to drain in the way that it was meant to.

Video: How To Stop Waste Backflow Coming Up Into Your Bath, Shower or Sink.

Remove Clogs

If you can, remove any clogs in the drainage system before doing anything else. Not only is it both easier and less expensive to clear a clogged drain than it is to install hardware or additional plumbing, but it will also show you if a clogged drain is, in fact, the cause of the problem.

There are many ways that you can clear a clogged drain. Plumbers often use a snake to physically remove any blockages that are present, but applying these methods requires access to the plumbing. Not every setup allows for this solution. You can also use a variety of chemicals made specifically to handle drain blockages.

Avoid Future Clogged Drains

Another way to avoid having water from the washing machine back up in the bathtub is to make sure that future clogs are kept to a minimum.

There are ways to filter wastewater before it enters the drainage line. Doing so can prevent the toughest clogs. Regular maintenance is also helpful. Many people our baking soda down the drain, followed by vinegar. The chemical reaction that takes place is often enough to loosen up debris, making it much easier to clear out.

Another way to avoid clogged drains is to be mindful about what goes down the drain. There are many things that can cause buildup inside of the plumbing. When the insides of the pipes are lined with grease and other sticky substances, many other particulates, lint, hair, and dirt can get stuck to the pipe.

Installing a Non-Return Valve

Another potential fix to the problem is a non-return valve. A non-return valve is an attachment that you can place onto the drainage pipe leading away from the bathtub. The device allows water to flow in only one direction. There is a valve that closes when water goes in the wrong direction which is a feature that stops backflow very effectively.

Installing the valve correctly will help you ensure that the device works as it should. To install your non-return valve, it is important to remember where the backflow is originating from.

When you get water from your washing machine backing up into your bathtub, it means that the washing machine is attached to the drainage line in between the bathtub and the main drain leading out of the house.

The non-return valve, therefore, should be installed onto the drainage line somewhere between the bathtub and the washing machine. This will stop all water from the washing machine from backing up into the bathtub.

Maintaining Your Non-Return Valve

An important consideration when installing a non-return valve is that it will require some maintenance from time to time. Non-return valves are very effective in blocking water flow from running the wrong way, but they do get clogged periodically.

Clogging happens especially frequently when a washing machine causes the water backup. Water from a washing machine has a lot of lint and other debris mixed in with the water that can build up on the inside of the non-return valve.

To clean the non-return valve, simply unscrew the cap on the top and clear out anything that could slow down your water flow. Once the non-return valve is clear, all that is left to do is cap it off and schedule your next routine maintenance.

How often the valve will need to be checked depends on a number of factors, but we have found that checking once every three months or so provides a good timeframe.

Alternatives to a Non-Return Valve

The idea of regular maintenance may not be an attractive one for some, as many prefer a more permanent solution. It is also not possible for many plumbing setups that don’t allow for easy access to the drainpipes. If you belong to that group, this section is for you.

The answer is surprisingly simple but it will require more effort than both installing a non-return valve and clearing clogs on a regular basis. The best and most permanent solution to the problem is to run new plumbing. The washing machine and the bathtub should each have their own drainpipes leading to the main wastewater outlet.

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Related Questions

How do you unclog a laundry tub?

Unclogging a laundry tub is very similar to removing clogs from any other type of drain. In many cases, it can even be simpler. The first thing that you should try is a plunger. Plungers work very well for blockages that are not too difficult.When plungers do not work, a snake – also known as an auger – is a great second option as it can reach far into the drain, physically dislodging anything blocking water flow. For some clogs, it is also possible to use very hot water with plenty of dish soap.

How do you unclog a main drain line?

The most efficient way to unclog a main drain line is to use an auger. To do this, you should first gain access to the main drain line by taking off the cap. This is usually located on the outside of the home. After taking off the cap, feed the auger cable down into the drain. Turn it on and wait for the drain to clear.

What do you do when your sewer backs up in the bathtub?

If your sewer backs up into your bathtub, it is time to call the plumber. The cause for this is often similar to what causes water from a washing machine to back up into your bathtub but the problem – the clogged drain – is much further away.It is usually very difficult to locate and clear clogs in the main sewer line but a plumber can do it quite easily using equipment designed to tackle the job.

Benjamin Wright
Benjamin Wright

Benjamin is a proud homeowner who loves to write about DIY projects and home improvement projects. Traveling, perfecting his home, and spending time with his family are just a few of the many things that keep him inspired.

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