Why does my washer smell like sewage? A Plumber’s Response

Sewage smell or sometimes smell of rotten eggs can start emanating from your washing machines, signaling something must be wrong with your washer.

Not only is the sewage smell not welcome, but it also makes the area where the washer is placed uncomfortably to live and work in. The unpleasant smell can also signal that you may be dealing with something potentially harmful, and if not addressed with urgency, it may be harmful to you and your family.

So, why does my washer smell like sewage? Your washer smells like sewage because of bacteria due to the build-up of dirt in your washing machine. It can also be due to clothing getting trapped on your washer without you noticing and starting to decay and develop mold and bacteria.

Plumber, Shawn Bucklew, owner of InHousingPlumbingCompany.com in Garland, Texas states that you will need to check the manufacturer’s manual to locate and clean the crevices and other openings to eliminate the sewage odor.

In this section, we will look at these reasons in-depth and analyze why your washer may smell like sewage and what you can do about it.

Why does my washer smell like sewage when I do laundry?

Nasty and unpleasant smells can sometimes emanate from your washer only when you are doing laundry. This can be caused by several factors such as:

  • Dry or damaged water trap that allows sewage smell to be released

When installing a washing machine, most people ignore the role a dry trap plays in ensuring that water in your washing machine is clean and instead look for a convenient drain line that is just a pipe that extends the washer. Failing to install the trap, however, comes with its own disadvantage by exposing your washer and washing area to sewer fumes resulting in sewage-like smells.

There is also a water trap located under your washer basin and drainpipes. If these water traps dry up, it creates a problem whereby the washer cannot prevent sewer gases from accumulating in your washing machine. The result is a sewage-like smell when using your washer.

The fortunate thing about dried water traps is they are easy to fix. You will only need to add water to replenish the water that has evaporated because of not using your washer for a long time.

A damaged drain trap, on the other hand, needs to be replaced. Fixing and seeking professional services to fix your dry water traps can also help prevent the smell.

  • Venting issues allow sewage smell to enter washer

Your plumbing design can also result in your washing machine smelling like sewage. If your drainage system, for instance, is not properly vented, then it becomes quite easy for sewer gases to make their way to your washing machine, and the moment you start washing your clothes, the sewerage smell fills your washer.
Even in instances where you have a professionally designed venting system on your drainage system, the sewerage smell can still emanate because of clogged pipes that prevent sewer gases from escaping your drainage system to the venting pipes. In a normal, working, unclogged system, you would expect these gases to be released into the air through openings in the roof, but that is not always the case.

In most circumstances, where clogs are the primary reason you are having a sewerage smell when doing laundry, it is important to contact professional help to help redesign or unclog your drainage system connecting your washer.

  • Dirty washing machine can smell like sewage

Your washing machine is also susceptible to dirt and failing to maintain a clean environment around it can result in clogging or dirt accumulating inside your washer, making it smell like sewage.

To avoid this, you need to unclog drainpipes and clean vent pipes. You can also use baking soda, distilled white vinegar and mineral oil to clean your washing machine.

Here is a video that shows how someone determined why their laundry room was smelling bad:

The washing machine smells when running

You may also notice that a sewerage-like smell is coming from your washer immediately after it starts running, and you need to figure out what you are dealing with before you can solve the problem with your washer.

In most instances, when this happens, it is because of dirt inside your washer or bacteria growing in your washer. Months or sometimes years of neglect and not cleaning your washer results in a build-up of dirt and bacteria on, under, or inside the rubber seal and in the crevices of the drum.

The build-up, combined with a wet environment, results in the growth of mildew, mold and bacteria over time.

How do you get rid of the sewer smell?

Addressing the unpleasant smell coming from your washing machine should be a priority. This is because not only does the sewage smell signal that your machine may need repair, but they also pose a health risk, and it is hard to tell what dangers may result because of the smell. I recommend Active Washing Machine Cleaner. To view on Amazon, click here.

To clean your washer, you will need arduous work and start by pulling back the rubber seal if you are dealing with a front-load washer to check for anything that might be trapped. Next, you will need to clean the seal. I recommend Finally Fresh Washing Machine Cleaner. Click here to view the pricing on Amazon. This should be done by using a solution of vinegar and water, which is amazingly effective in removing soap scum, mold, and debris. Alternatively, you can also opt to use bleach instead of vinegar to clean the seal.

Next, you will be required to run your washer on the hottest and largest setting, which for the case of a front-load washer, you will need to add at least a third cup of baking soda to the drum and a solution of vinegar and water to the detergent tray.

Your approach for top-loading washing machines, however, will be different, and the best combination of the washing solution is half a cup of baking soda and two cups of distilled white vinegar, which should be half full.

To make sure that your washing machine does not produce a sewage-like smell in the future after washing, you are required to dry out the interiors and leave the machine open until it dries up. You should also consider wiping dry after every use, especially the rubber seal area on the front-loading washers. Also, following the manufacturer’s manual when maintaining your washer goes a long way to ensure that you do not deal with the same problems in the future.

Sewer smell in the laundry room after rain

In most cases, rain is always welcomed and helps clean the air around us and improve the environment by removing dust and keeping everything green.

However, for many homeowners, rain is not always a welcome guest, and many homeowners worry about their roof and shingles with every drop of rain that hits the ground. The potential possibility of the floor leaking through the roof and causing damage to furniture and interior design is always something to worry about for these homeowners.

However, for some homeowners, it is the sewage-like smell in the laundry room that most concerns them. The smell is unpleasant and can be caused by several plumbing issues, washing machine maintenance, and the general design of the laundry room. Some of the reasons that causes this smell are: –

  • Clogging of pipes

Heavy rains can overwhelm plumbing done in your laundry room, resulting in clogging of water pipes. When this happens, dirt, mold and bacteria start to accumulate, resulting in your laundry room smelling like a sewer.

To prevent this, you need to ensure that your laundry room’s plumbing is done by professionals and can handle a drastic increase in water to avoid clogging.

  • Sewer gas

A mixture of household wastewater and products going down your drain can result in sewer gases in your sewerage system. These gases can make their way into your laundry room after heavy rains and can be released in case there are pipe leakages.

These gases can be both toxic and non-toxic, and the mixture produces very bad smells, which include a combination of sulfur dioxide, ammonia, hydrogen sulfide and other gases.

Sewer gases are a product of faulty plumbing systems in your laundry room, and the only way to correct the problem is by fixing the pipes and plumbing.

  • Damaged water trap

A water trap is a critical piece of plumbing infrastructure that prevents sewer gas from leaking. To prevent gas sewers from finding their way to your laundry room during rainfall, you should make sure they are not damaged, and in cases where they are damaged, you can either fix them yourself or consult a plumber.

  • Floor drains

If your laundry room has floor drains, then you should consider keeping them fixed at all times to avoid water and gas sewer leakage.

The washing machine smells worse after cleaning

Cleaning washing machines can sometimes result in giving awful and unpleasant smells. This becomes a problem, especially if you rely on the washer for your day-to-day laundry, where the smell can be transferred onto your clothes.

The unpleasant smells can be caused by several reasons, including mold, dirt and bacteria. The load introduced in the washer, such as hair, oil, detergents, chemicals, oils, may also contribute to the unpleasant odor. Using hard water to clean the washer can also contribute to the smell due to the clogging of the drainage system by the scum from the water.

Another reason your washer smells worse after cleaning is that you usually loosen the dirt and grime while washing without flushing it completely from the insides of the machine. This can also manifest in black specks of dirt in your washer after cleaning or nasty colored wastewater while cleaning.

So how do you ensure your washer does not smell after cleaning it? Fortunately, the easier solution is by running a second clean cycle to remove any dirt that might have accumulated on your washer, which the first clean cycle was not able to capture. A simple hot wash can also clean the oily parts and remove dust, grime, and bacteria in the washer.

In cases where you have had multiple cleaning cycles and the smell just won’t go away, you will need to check on the drain to make sure there is no stagnant water. If the drain is clear, then you should consider contacting the manufacturers and informing them of your problems.

You should also consider a cleaning service, which cleans the inside of the washing machine. A simple service wash can, for instance, include running the machine empty at a hot temperature to get rid of bacteria.

Cleaning the seal, which is mostly exposed to dirty laundry, water, and chemicals all day long, can also help you avoid the unpleasant smell after cleaning. You should also check if the seal has developed molds, which can also result in a nauseating smell.

Below Is a Chart Listing off Ways Users on Plumber Forums Have Reportely Cleaned Their Washers:

How to clean inside of washerPercentage of total results
Running your washer on its highest setting can help sanitize and remove dirt from the inside of your washer.30.77%
Using a preferred bio powder can make a significant difference when cleaning the inside of a washer. A popular bio powder is Rockin’ Green’s Active Wear Laundry Detergent.19.23%
Users have found that using a small amount of vinegar along with a hot water cycle can easily clean your washer.23.08%
By putting a cap of bleach inside of a washer and running a cycle, you can thoroughly sanitize the interior of your washer.15.38%
A surprisingly lesser chosen solution by forum users was to use a washer cleaner of choice to sanitize your washer. 11.54%
Data derived from multiple plumbing and home maintenance forums

How to clean smelly washing machine top loading

Top load washing machines are prone to dirt, mold and bacteria and need to be cleaned regularly to avoid a sewerage-like smell. 

With every piece of clothing that passes through them, small residues of dirt, bacteria and fabrics that, over time, develop build-up resulting in unpleasant odors. Fortunately, cleaning a top load washer is not complex. Here is how you can do it.

  1. Start by emptying your washer. Make sure your washer drum is empty before starting the cleaning process. You should also ensure that your dispenser is also empty by removing any detergents and fabric softeners that might still be in the reservoirs.
  1. Select the water temperature that is appropriate for your cleaning. This should always be set to the hottest water setting available for effective cleaning of molds and killing of bacteria.
  1. Next step is to fill your washer with water. Ensure that your washer is full of hot water but ensure that the cleaning cycle is not running.
  1. Add Chlorine bleach and run a complete washer cycle. You can do this by allowing the washer to run through its longest wash, rinse and spin cycle.
  1. Next, you can clean detergent and fabric softener dispensers, adding hot water again, this time combined with four cups of distilled white vinegar.

6. Next, rerun the cleaning cycle, and finally, clean the outer housing of your washing machine.

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Aron Blake

I am the lead copywriter on Homezesty and the Webmaster. I have a lot of experience in home renovations and the creation of style. I enjoy writing and sharing my tips on how to create the best living environment. My Linkedin Profile, My Twitter Account

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