How to Clean a Washing Machine and Remove Musty Odors
There is a distinct irony in a washing machine that smells like a damp, forgotten basement. You throw your dirty laundry into a machine expecting fresh, clean garments, only to pull out damp towels and shirts that carry a faint, sour odor. Over time, this musty smell can transfer directly to your fabrics, ruining your laundry day and leaving you wondering how an appliance designed for cleaning can get so dirty. If you are dealing with a smelly washing machine, you are not alone. Modern high-efficiency (HE) washing machines are highly prone to trapping moisture, soap scum, and organic debris. Fortunately, resolving this issue does not require calling a professional or buying expensive specialty tools. With a few common household items and a little bit of elbow grease, you can deep clean your washing machine and restore its fresh scent. This comprehensive guide will walk you through the exact steps to clean both front-load and top-load washing machines, address hard-water mineral deposits, navigate tight space constraints in apartments, and keep your appliance running efficiently for years to come. Quick Answer: How to Clean a Smelly Washing Machine To quickly eliminate musty washing machine odors, run a hot cleaning cycle with one cup of liquid chlorine bleach to sanitize the drum. Next, pull open the rubber door gasket (on front-loaders) and wipe away trapped hair, slime, and debris using a microfiber cloth. Remove the detergent dispenser drawer and scrub away soap buildup with warm water and a few drops of liquid dish soap. Finally, locate, drain, and clean the pump filter at the bottom front of the machine, which is often the primary source of standing water odors. To prevent the smell from returning, always leave the washer door open between cycles to allow the interior to dry completely.
Why Does Your Washing Machine Smell Musty?
Before diving into the cleanup process, it helps to understand why your washing machine smells in the first place. This understanding will help you prevent the problem from returning. Modern washing machines, especially high-efficiency models, use significantly less water than older appliances. While this is excellent for utility bills and the environment, it presents a unique cleaning challenge. Because there is less water flushing through the system, detergent residue, fabric softeners, body oils, hair, and lint do not always wash completely down the drain. Instead, they cling to the drum, the rubber seals, the detergent drawer, and the internal plumbing. This mixture of soap scum and organic waste forms a slick, slimy layer known as biofilm. Biofilm is the perfect breeding ground for mold, mildew, and bacteria. When you keep the washing machine door closed between cycles, you seal this moisture and biofilm inside a dark, warm environment. Within days, mold spores multiply, resulting in that classic sour, musty odor. Furthermore, about 85 percent of US homes have hard water. Hard water contains high concentrations of calcium and magnesium minerals. When these minerals react with laundry detergent, they create a stubborn curd or scale that sticks to the internal components of your washer. This rough mineral scale acts like Velcro, trapping even more soap residue, body oils, and bacteria, which accelerates the development of musty smells. Materials Needed to Clean Your Washer Before you begin, gather the necessary supplies. You likely have most of these items in your utility room or kitchen pantry already. Liquid chlorine bleach (for sanitizing and killing mold spores) White vinegar or citric acid powder (for breaking down hard-water scale) Dawn liquid dish soap (excellent for cutting through sticky fabric softener buildup) An old toothbrush or a soft utility scrub brush Several clean microfiber cloths A shallow pan and an old towel (for catching water from the drain pump) Rubber gloves to protect your hands Safety glasses (recommended when working with bleach) Step-by-Step Instructions to Clean a Front-Load or Top-Load Washing Machine This step-by-step process is divided into logical sections. Be sure to perform these steps in order to ensure you do not spread grime back onto areas you have already cleaned.
Step 1: Empty the Drum and Run a Sanitizing Bleach Cycle
Start by ensuring the washing machine drum is completely empty. Do not leave any clothes, rags, or loose items inside. For front-load and top-load machines, select your washer's Clean Washer cycle. If your machine does not have a dedicated cleaning cycle, select the hottest water temperature setting, the heaviest soil level, and the longest wash cycle available. Add one cup of liquid chlorine bleach directly to the empty drum (for top-loaders) or fill the bleach compartment in your detergent dispenser drawer to the maximum fill line (for front-loaders). Start the cycle and let it run completely. The hot water combined with the chlorine bleach will sanitize the interior surfaces, break down biofilm, and kill active mold and mildew spores.
Step 2: Scrub the Detergent Dispenser Drawer
While the cleaning cycle is running, you can work on the detergent dispenser drawer. This area is a major hotspot for mold because liquid fabric softeners and detergents often leave behind a sticky, gummy residue. Fully extend the dispenser drawer. Look for a small release tab (usually marked PUSH or located near the fabric softener compartment), press down on it, and gently pull the drawer completely out of the machine. Take the drawer to a utility sink or kitchen sink. If you live in an apartment with limited sink space, a bathtub or a large plastic bucket works perfectly. Disassemble any removable pieces, such as the fabric softener or bleach cups. Fill your sink or bucket with warm water and add a few drops of Dawn liquid dish soap. Let the drawer parts soak for 10 minutes to loosen the hardened soap residue. Using an old toothbrush, scrub away all traces of blue, green, or white soap buildup, paying close attention to the small crevices, corners, and siphoning tubes. Before sliding the drawer back in, look inside the empty drawer cavity on the washing machine. You will likely see mold and soap scum clinging to the top and back walls of the recess. Wipe this area clean with a damp microfiber cloth sprayed with a mild soap solution. Once clean, dry the cavity, reassemble the drawer, and slide it back into place.
Step 3: Clean the Rubber Gasket (Front-Load Only)
If you have a front-load washing machine, the large rubber door seal, or gasket, is the most common culprit behind musty odors. Water frequently pools in the folds of this gasket after a wash cycle, creating a prime habitat for black mold. Put on your rubber gloves and open the washer door wide. Gently peel back the folds of the rubber gasket with your fingers. Inspect the interior channel for foreign objects like hairpins, coins, buttons, and pet hair, and remove them. Mix a solution of one cup of warm water and a few drops of Dawn dish soap. Dip a microfiber cloth into the solution and thoroughly wipe down the entire inside of the rubber fold, removing slimy gray or black buildup. If you spot stubborn black mold spots that do not wipe away, do not scrub them with an abrasive pad, which can tear the rubber. Instead, saturate a strip of paper towel or an old rag with a 50/50 mix of water and liquid bleach. Lay the damp cloth directly inside the fold of the gasket over the mold spots and let it sit for 30 to 45 minutes. Remove the cloth, scrub gently with a soft toothbrush, and rinse thoroughly with clean water. Dry the gasket completely with a dry towel when finished.
Step 4: Drain and Clean the Pump Filter
Most modern front-loading washing machines and some newer top-loaders have a drain pump filter designed to catch lint, coins, hair, and keys before they damage the water pump. If you have never cleaned this filter, it is highly likely full of stagnant, foul-smelling water and decaying debris. Locate the access door for the filter, which is typically on the bottom front of the machine. If you live in a tight rental space or a stacked washer-dryer closet, you may need a flashlight to see it clearly. Lay down an old towel on the floor directly beneath the access door to protect your flooring. If you have hardwood or luxury vinyl plank flooring, this step is critical to prevent water damage. Open the access door. You will see a small hose (the emergency drain hose) and a large round dial (the filter cap). Place a shallow pan or container under the emergency drain hose. Pull the plug out of the hose and allow the trapped water to drain completely into the pan. This water can smell incredibly foul, so work quickly and keep a trash bag nearby. Once the water stops flowing, plug the hose and push it back into place. Now, slowly turn the large filter dial counterclockwise. Be prepared for a small amount of residual water to spill out onto your towel. Pull the filter assembly completely out of the machine. Remove any tangled hair, lint, coins, or paper debris. Take the filter to the sink and wash it thoroughly with warm water and a splash of dish soap. Reach your hand inside the filter housing chamber on the machine to feel for any trapped debris or coins. Wipe the interior of the chamber with a damp rag. Insert the clean filter back into the chamber, turning it clockwise until it is hand-tight and secure. Close the access door.
Step 5: Wipe Down the Exterior and Surrounding Area
To finish the deep clean, wipe down the exterior of the washing machine. Use a damp microfiber cloth with a mild soap solution to clean the control panel, the door handle, and the top of the machine where spilled detergent often accumulates. If your laundry area is located in a damp basement or a small, unventilated apartment closet, dust and pet hair can quickly build up around the back and sides of the machine, restricting airflow. Vacuum these dusty areas to keep the appliance running cool and efficiently.
What NOT to Do When Cleaning Your Washing Machine
While cleaning a washing machine is relatively straightforward, certain common mistakes can damage your appliance or create safety hazards. Do not use abrasive cleaning powders or steel wool pads. These can scratch the stainless steel drum or the plastic surfaces of your machine. These tiny scratches create microscopic crevices where bacteria and mold can cling even more easily, making future odors worse. Do not pour dish soap directly into the washing machine drum for a cycle. While Dawn is excellent for hand-scrubbing removable parts, putting it inside the machine's wash cycle will cause excessive sudsing (oversudsing). This can overwhelm the pump, leak onto your floor, and throw error codes on your machine's control panel. Do not use vinegar in every single wash cycle. While white vinegar is a popular natural fabric softener and deodorizer, it is highly acidic. Over time, constant exposure to vinegar can degrade the rubber seals, hoses, and gaskets in your washing machine, leading to costly leaks. Do not ignore your manufacturer's manual. Always consult the user manual for your specific brand and model before removing parts or using specific chemical cleaners, as doing so could void your warranty. Safety and Material Warnings Your safety is paramount when cleaning any household appliance. Please keep the following warnings in mind: NEVER mix bleach and vinegar. This is the most critical safety rule when cleaning a washing machine. Mixing chlorine bleach with any acid, including white vinegar, lemon juice, or citric acid, produces toxic chlorine gas. Inhaling chlorine gas can cause severe respiratory distress, coughing, watery eyes, and chemical burns. Ensure proper ventilation. When running a hot cleaning cycle with bleach, open nearby windows, turn on your bathroom exhaust fans, or open the laundry room door to keep fresh air circulating throughout your home. Protect nearby flooring. If your laundry room features natural stone flooring, such as slate, marble, or travertine, be extremely careful when handling vinegar or citric acid. Even a few drops of these acidic liquids can etch the surface of natural stone, leaving permanent dull spots. Lay down protective towels or plastic sheeting before you begin. Follow product labels. Always read the safety instructions on your cleaning products. Wear protective gloves and eyewear to prevent chemical splashes, especially when working with concentrated bleach. Maintenance Tips to Prevent Musty Odors Once your washing machine is fresh and clean, you can prevent musty odors from returning by adopting a few simple laundry habits. Leave the door open. This is the single most effective habit you can adopt. When the machine is not in use, keep the door or lid slightly ajar. This allows fresh air to circulate inside the drum, drying out any residual moisture and preventing mold growth. Remove wet laundry immediately. Do not leave wet clothes sitting in the washing machine for hours or overnight. Transfer them to the dryer or clothesline as soon as the cycle ends to prevent musty smells from developing in both your clothes and the machine. Use the correct amount of HE detergent. Most modern washing machines require high-efficiency (HE) detergent, which is formulated to produce fewer suds. Read the detergent label carefully and use only the recommended amount. As a general rule, you only need about one to two tablespoons of 2x concentrated liquid detergent per load. Using too much detergent does not get your clothes cleaner; instead, it leaves a sticky residue inside the machine that feeds mold. Skip the liquid fabric softener. Liquid fabric softeners work by coating fabric fibers with a thin layer of lubricating chemicals. This same coating builds up inside your washing machine's drum and drain pipes, forming a sticky layer that traps bacteria and hair. Consider switching to wool dryer balls or white vinegar in the fabric softener dispenser drawer to soften clothes naturally. Run a monthly maintenance cycle. Do not wait for your washing machine to start smelling before you clean it. Mark your calendar and run a hot self-clean cycle with bleach once a month to keep biofilm from forming. Manage humidity in tight spaces. If your washing machine is located in a small apartment utility closet or a damp basement, consider running a small dehumidifier nearby. Keeping the ambient humidity low will help the interior of your machine dry out much faster between washes.
Frequently Asked Questions
Can I use baking soda and vinegar together to clean my washing machine?
While baking soda and vinegar are popular natural cleaners, mixing them together in the washing machine is not highly effective. When combined, the acid (vinegar) and base (baking soda) neutralize each other, producing carbon dioxide gas and saltwater. While the initial bubbling reaction can help physically loosen some light debris, the resulting liquid has very little cleaning power. It is much more effective to use them separately: run a hot cycle with vinegar to dissolve hard-water minerals, followed by a separate cycle with baking soda to deodorize.
How do I clean a washing machine that has hard water buildup?
If you live in a region with hard water, chlorine bleach will not dissolve the mineral scale inside your machine. To address hard-water scale, run a hot cycle using one cup of citric acid powder or two cups of white vinegar instead of bleach. The acid will break down the calcium and magnesium deposits. Remember, never run this acidic cycle with bleach in the machine.
Why does my brand-new washing machine smell bad?
If your brand-new washer has a musty smell, it is often due to standing water left in the pump from factory testing, which may have sat in transit or storage for weeks. Running a single hot cycle with bleach will quickly resolve this issue. If the smell is a strong plastic or chemical odor, this is normal outgassing from new rubber and plastic parts and will fade after a few wash cycles.
How often should I clean the drain pump filter?
For normal household use, you should clean the drain pump filter every three to four months. However, if you have multiple pets that shed heavily, or if you frequently wash heavily soiled work clothes, you may need to clean the filter once a month to prevent clogs and odors. Is it safe to use dishwasher tablets to clean a washing machine? While some viral internet tips suggest using dishwasher tablets in a washing machine, it is generally not recommended. Dishwasher detergents are highly concentrated and designed to break down food grease, not laundry soils. They can produce excessive foam or leave behind residues that are difficult to rinse out of a washing machine's internal plumbing. It is much safer and more effective to use products specifically formulated for washing machines, or standard liquid chlorine bleach.