If you forget washed laundry in the drum for a few days, the machine afterward smells of damp and slightly rotten cotton. But a washing machine can smell even in homes where the laundry comes out on time. Dirt and small particles of fabric gradually get packed in between the rubber gasket and the body of the machine, into the filters and into other hard-to-reach places.
Nobody is protected from this problem, and owners of all kinds of models in Escondido ask the same question. There is some good news: most of the time you can clean the machine yourself, without calling in a technician. Below is where mold in a washing machine comes from, where it grows, how to get rid of it and what to do so it does not come back.
Where the Musty Smell in a Washing Machine Comes From
Before doing anything about a bad smell, you need to understand why it shows up. There can be several reasons:
- Dirt and fabric remnants. They collect in the door seal, the filter and the drain system. If you often wash clothes at low temperatures, grease, dirt and detergent do not dissolve completely and settle inside the machine.
- Soap and detergent. The excess settles on the walls of the drum and in the detergent drawer. This matters most if you add more powder than needed.
- Mold and fungus. These organisms multiply quickly in a damp environment. If the machine is not aired out after each wash and the seal is not wiped, water stands in the washer all the time.
- Standing water in the drain system. The water left in the hoses and the filter goes bad and smells.
- A closed door. Thanks to the seal, the door closes tightly against the body, and that stops any airing out. The result is a warm, damp environment that suits bacteria, and they are hard to get rid of later.
- Dirty laundry stored in the drum. Especially damp laundry. It is better not to: it causes a rotten smell that is hard to remove afterward.
- Washing at low temperatures all the time. At temperatures below 140°F many types of bacteria and fungi do not die and stay in the machine after the wash.
The warm, damp environment inside a washing machine is an ideal incubator for bacteria, fungi and mold. These get into the machine together with dirty laundry, especially if you wash kitchen towels, work clothes or children's things.
Black mold, which often forms on the rubber door gasket and in hard-to-reach spots of the drum, deserves special attention. Mold spores travel easily through the air and can settle on washed laundry. For people with weakened immunity, small children and older people, contact with such laundry can be especially unpleasant. A musty smell is not just a discomfort - it is a signal that unwanted biological processes are going on in the machine. The stale odor can soak into fabric, and even after several washes things can keep the smell. This is especially true of natural fabrics like cotton and linen, which absorb moisture well.
What Different Smells Mean
The smells coming from a washing machine differ quite a lot, and each one has its own cause.
- Damp or mold. The moisture inside the machine helps fungus and bacteria multiply. Most often this happens in the folds of the rubber seals, in the detergent drawer and in other places where water stands. Even a gasket that looks clean at first glance can turn out to be a breeding ground for mold if the folds are not cleaned and wiped in time.
- Rot. Leftover dirt and lint build up in the filter, the drain system or the drum and start to decompose.
- Chemicals and detergent. Too much powder and fabric softener settles in the drawer, the drum or the tubes, and over time it can go stale and smell bad.
- Sewage. The drain hose may be connected incorrectly, or there may be a clog in the drain system.
- Rotten eggs. This comes from bacteria that multiply in standing water inside the machine or the drain system and give off hydrogen sulfide.
- Burning or melting plastic. The heating element or other electrical parts may have overheated. Unplug the machine right away. Do not try to fix the problem yourself; have a technician diagnose it.
Where Mold Grows in a Washing Machine
The Door Gasket
The rubber door gasket is one of the most vulnerable places in a washing machine. It is built with folds that keep the door watertight when it is closed. But it is exactly in these folds that water mixed with dirt, lint and detergent stays after every wash. If the gasket is not wiped after each cycle, this mix becomes food for bacteria.
A typical mistake is using too much fabric softener. Softener is oily and does not rinse well off rubber. Over time a sticky film forms on the gasket, and dust and dirt cling to it. Plain water will not remove that kind of buildup anymore.
The Detergent Drawer
The detergent drawer is a place people often forget about. Many simply pour powder into it and never take it out for cleaning. Leftover powder, gel and softener collect in the compartments, mix with water and turn into a sticky mass. Over time this mass gets covered with a black film of mold. Mold in the washing machine drawer is especially unpleasant because during the wash the water carries spores from the drawer straight into the drum with the laundry. As a result, washed clothes can smell musty even if the machine looks clean from the outside.
The Drum
The inside of the drum can look clean, but dirt often collects in the water holes and between the ribs. Look the drum over in good light, turning it by hand. If you notice dark spots or film, they need to be removed.
The Drain Filter
The drain filter catches small objects that get into the machine: hair, coins, pet fur and so on. All the water from the drum passes through it. Even while water is still getting through, the organic leftovers stuck in the filter start to decompose and give off a rotten smell. This smell rises through the drain hose and gets into the drum.
How to Get Rid of Mold in a Washing Machine
You can use store-bought cleaners or household products. Below is the whole process using citric acid, soap, a brush and rags.
Cleaning the Detergent Drawer
- Unplug the machine. Take out the drawer as described in the manual for your model. Usually you press a latch (often marked PUSH) and pull the drawer toward you. Some models have removable dividers inside the drawer - take them out and wash them too.
- Wash it. Rinse the drawer under running water with a brush and soap. If the buildup is stubborn, soak the drawer in a citric acid solution for 30-60 minutes: about 4 teaspoons of citric acid per quart of hot water.
- Clean the slot. Rinse the drawer under running water to remove the citric acid. Clean the compartment the drawer sat in with a brush or a cloth dampened in cleaner or citric acid solution, then wipe it with a clean cloth. Water inlet holes in that slot collect dirt and mold too.
- Dry it. Let the drawer dry completely before putting it back. A damp drawer is a risk of new mold appearing quickly.
Cleaning Mold in Washing Machine Rubber
Sand, hair, threads and other dirt build up quickly between the gasket and the body, so water alone is not enough to clean it. Mold and other microorganisms that appear on the gasket over time cannot be removed with water alone either.
Besides store-bought products, you can use liquid soap, citric acid, baking soda or sodium percarbonate, a safe oxygen bleach. Choose whatever you have on hand:
- Citric acid: a quart of hot water and about 4 teaspoons of citric acid.
- Oxygen bleach: a quart of hot water and six teaspoons of sodium percarbonate.
- Liquid soap: a cup of warm water and a third of a cup of liquid soap.
- Baking soda: a cup of warm water and half a cup of baking soda.
The cleaning process:
- Unplug the machine. Put on gloves and mix the solution.
- Fold back the gasket and wipe it with a damp cloth soaked in the solution. A microfiber cloth works better than a sponge, since a porous surface picks up sludge worse.
- Get into the folds. If the dirt is heavy and hard to reach by hand, use a soft toothbrush or wrap a cloth around your finger. Leave the solution on the gasket for 20-30 minutes before rinsing.
- Know the limit. If mold has eaten into the rubber, keep in mind that it cannot be removed - the gasket has to be replaced as a whole.
- Rinse. Run an empty rinse to remove the leftover solution and dirt from the seal, or clean the drum after you finish with the gasket.
- Wipe it dry. Do this with a dry cloth after every wash.
Vinegar and chlorine products can damage the rubber seals, so check your machine's manual before using them. Chlorine bleach works against mold and bacteria and removes black spots from rubber, but with frequent use it can damage rubber seals, plastic parts and metal surfaces. Use it only on specific spots: put a small amount on a cotton pad, hold it on the spot for 10-15 minutes, then rinse well with water. Some manufacturers call for liquid chlorine bleach in the bleach dispenser on the clean cycle and others forbid it, so follow your machine's manual. After using it, air out the room and rinse the treated surfaces with water.
Do not let bleach come into contact with other cleaning products, especially acids such as vinegar or citric acid - this can release a toxic gas.
For larger areas of mold in the house, the EPA's guidance on mold cleanup at home is a good reference.
Cleaning the Drum
Most modern washing machines have a self-clean function. It is a cycle designed to remove insoluble dirt stuck to the tub and the drum, using only hot water and high spin speeds. If your machine has it, use it at least once every six months. Some manufacturers program machines so that self-clean starts automatically after a set number of washes, or a special indicator signals that it is time to run it. Read the manual for your model first.
- Run self-clean. If your model supports it, start it. Often you have to hold two buttons at once - see your manual.
- No self-clean? Use the hottest cycle. Run an empty cycle on the hottest setting your machine has, such as Sanitize or Heavy Duty. You can add half a cup to a cup of citric acid or a store-bought cleaner to the detergent drawer, if this does not go against the machine's manual.
- Rinse. When the cycle ends, run a rinse.
- Wipe. Wipe the inside of the drum and the gasket with a soft cloth to remove leftover moisture.
- Leave the door open to keep damp and mold from coming back.
Never add laundry during a cleaning cycle. The high temperature can damage fabric, and the laundry will soak up the dirt and scale washed out of the machine. Never use metal brushes, abrasive powders or harsh solvents on the drum either: they can scratch the stainless steel, and even more dirt will collect in the scratches.
Cleaning the Drain Pump Filter
Many manufacturers recommend cleaning the debris filter several times a year. Threads, lint, buttons and things forgotten in pockets collect there.
- Unplug the machine. If it just ran a hot wash, let the water cool first.
- Find the filter. It is usually at the bottom front of the machine, behind a plastic door or panel.
- Lay a towel down. Open the panel and spread a rag in front of and under the machine in case the filter drips.
- Drain the water. Set a small container underneath and let the water out of the emergency drain hose. It is next to the filter cap and closed with a small plug. Usually 1-2 cups of water come out, more if the machine did not drain after the last wash.
- Unscrew the filter cap slowly, counterclockwise. Debris will come out together with the water.
- Remove the debris you see, including what is left in the filter housing. Rinse the filter under running water and wipe the inside of the housing with a dry cloth.
- Put the hose and filter back in place.
Vinegar and Baking Soda
If a cleaning cycle did not help, you can try home remedies.
- Vinegar cycle. Pour two tablespoons of plain white vinegar into the detergent drawer and run the longest program on the hottest setting. If your washer allows it, pause the program after ten minutes and wait about an hour so the vinegar has time to work, then resume it and let it finish. At the end, take out the filter and rinse it well. Treat the machine with vinegar no more than once every four months: frequent use can make rubber seals stiff.
- Soda, then vinegar. Pour seven tablespoons of baking soda into the detergent compartment and run a short cycle on warm with an empty drum. When it ends, run the machine again, this time with vinegar, on hot. The order matters: if you run soda and vinegar at the same time, they react with each other and the cleaning works worse.
After vinegar the drum may smell of it. Just leave the door open and air out the room, and it goes away quickly.
Mold in a Front Loader vs. a Top Loader
The rubber gasket is the most problem-prone spot in a front-loading washing machine. Water stays in its folds after every wash, mixes with dirt, lint and detergent, and if the gasket is not wiped, mold forms in it quickly. That is why mold in washing machine front loader gaskets is the most common complaint.
A top loader is cleaned on the same principle. The difference is that the detergent drawer and the filter can be in other places, so look for them in the manual for your model. If there is no filter at all, it usually means it is connected to the pump and cleans itself automatically.
How to Keep Mold Away
- Leave the door open after washing so the drum dries. Leave it slightly open for at least 2-3 hours, ideally until the inside is fully dry. If the laundry room is small and the open door is in the way, leave it ajar at least overnight. Leave the detergent drawer slightly open too.
- Wipe the gasket dry with a dry cloth after every wash.
- Use less detergent. Oddly enough, the more detergent you use, the worse the machine washes and the faster the smell appears. Modern powders and gels are concentrated, and good washing takes much less than many people are used to. Follow the dosing on the package. If powder does not wash out of the drawer completely, adjust the amount.
- Do not keep laundry in the drum. If you cannot wash dirty laundry right away, use a ventilated hamper. Never put damp things in closed containers.
- Run a hot wash regularly. It helps to run a hot wash at least once every week or two. It can be bedding, towels, kitchen linens, or just an empty run with citric acid or a cleaner.
- Check the filter and the gasket for dirt, rinse and air out the detergent drawer, and do a preventive cleaning of all parts at least once every six months.
When the Smell Means a Leak Under the Machine
A rubber seal that is constantly compressed loses its elasticity, and cracks appear in it where dirt collects. This not only causes a smell, it also makes the machine less watertight, so water may seep out during a wash. Old, worn parts are not just a source of odor but also a leak risk.
If the machine is clean and the musty smell in the washing machine area stays, check the floor under and behind it. Water that seeps out unnoticed soaks the subfloor and the wall, and mold can grow there where you cannot see it. Our guide on preventing mold after a plumbing leak covers the first steps. When the floor or drywall is already wet, it needs water damage restoration and drying, and visible growth beyond the machine is a job for professional mold remediation in your home. If the laundry room has to be emptied while it dries, pack-out services for your belongings keep your things out of the way.
To learn more about our restoration team, read what homeowners say in reviews, browse more articles in our blog, or go back to the Escondido restoration company home page.