Toilet Bubbles When Washer Drains

Sometimes our toilet produces sounds that put fear into our bones: the gurgling, the bubbling, the burping. Although it may seem as if a demon will pop out, the real reason is the air going through the pipes.

When washing your clothes, the machine may push the air back into the drain. In the case of a blocked drain, the air still manages to find its way through the closest pipe, which can result in all kinds of weird sounds. The mechanism resembles creepy whistling since it’s pushing a large amount of air through a small hole.

In this article, we will talk about why the toilet gurgles when the washer drains. We will list some of the most common reasons behind this issue and what you can do if you see the toilet bubbling when the washer drains.

Why Does My Toilet Bubble When My Washer Drains?

The toilet bubbles, gurgles, and burps are caused by negative air pressure in the pipes. As the washing machine drains, it pushes air back through the pipes, causing bubbles to form in your toilet.

But why does this happen in the first place?

Well, there are several possible causes. Your drains or vent pipe, or sewer lines may be blocked, the washing machine drain may not be properly installed, or the drains may all be connected.

Let’s tackle each of these causes one by one and see what you can do to address them.

Partial Clogs

Sometimes the main drain of the washing machine can partially clog. As the air flows through the drain, this clog can cause gurgling sounds and bubbles. As the washer drains, the restricted water path forces the air and water back into the pipe, and the water keeps going but at a different rate.

This can result in a backflow that will lead to toilet bubbling and gurgling. Eventually, you may notice that a similar sound is coming from your bathtub and sink as the air is searching for routes to escape.

Vent Pipe Clog

The vent pipe is a vertical line connecting the sewer pipes and the drains. It lets the air flow through the drains while allowing water to flow normally. If there is a blockage in the vent pipe, the plumbing system won’t work correctly, resulting in a bubbling and gurgling toilet.

Water needs airflow to drain properly. A clogged vent pipe will force the air back through the drain, and it will escape from the closest opening, usually the toilet drain, causing bubbles.

The vent pipe usually goes through the roof, and debris and dirt may get in if there is no proper protection. This reduces the number of possible routes the air can take, causing your toilet to bubble and gurgle.

If bubbling and gurgling noises have been accompanied by strange and unpleasant smells, you’re probably dealing with a vent blockage.

Connected Drains

If the gurgling noises and toilet bubbling occur while the machine is washing rather than draining, you might be dealing with connected drains.

Washer Drain Isn’t Properly Installed

If the washer drain is not properly installed, the washing machine releases too much air too fast under high pressure, causing gurgling in your toilet.

Many people go over the manual installation of pipes, not paying attention to whether everything is working properly.

How to Put a Stop to Bubbles When Washer Drains?

Above, we listed some problems that may be causing toilet bubbles when the washer drains. In this section, we’ll offer possible solutions that should stop the bubbling and gurgling once and for all.

P-Trap Drain Installment

When a washing machine doesn’t have a properly installed draining system, it will cause problems in the drain or connected drains, resulting in gurgling, bubbling, or burping. Installing a P-Trap Drain will likely solve the problem and eliminate the unpleasant sounds for good.

If this doesn’t result in a solution, a trip to the roof may be necessary to clean the main vent stack.

Removing the Clogs

If the cause of gurgling and bubbling are clogged pipes, unclogging is the right option. The machine drain unclogging is more complicated than unclogging the toilet drain.You can do it with a bucket of boiling water mixed with baking soda. Pour the mix into the drain through a funnel. If you have reason to think your washing machine drain is clogged, check out this helpful video on how to deal with it.

Dealing with clogs usually doesn’t require professional help, but if you can’t beat them after repeated trials, it might be a good idea to call a plumber, as the problem might be more serious than you think.

Clearing the Vent

Clearing the vent can be a dangerous project, as it requires climbing on the roof. If you’re inexperienced with such DIY house projects, we recommend you call a professional.

If you decide to do it by yourself, it would be good to have some assistance, as you’ll need to observe the inside of the vent first with a flashlight to see if anything is in there. Then, you can remove the debris by hand (if it’s within reach) or with a garden hose.

Final Words

Vents, traps, and cleanouts are also important parts of the draining system. Vents on the roof let the air into the pipes, while traps are found on every fixture (e.g., below the sink or behind the toilet), preventing waste smells from leaving the pipes. Cleanouts are the access points to the main sewer line placed outside your home.

For a draining system to work properly, all parts need to be functional and in sync. One failure will impact the whole drain system, which is why it’s sometimes difficult to diagnose the source of a problem.

There are several possible causes that can create toilet bubbles and gurgle. If you’re planning to tackle the problem yourself, make sure to arm yourself with patience and go through all the steps we have described for the most accurate possible diagnostics.

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