How To Deep Clean A Washing Machine Drum To Eliminate Mildew Smell

A musty, moldy odor coming from your washing machine is more than just unpleasant—it’s a sign of microbial buildup in the drum, seals, and internal components. Over time, moisture, detergent residue, fabric softener, and lint create a breeding ground for mildew and bacteria, especially in high-efficiency (HE) front-load washers. Left untreated, this not only affects the scent of your laundry but can also compromise hygiene and shorten your appliance’s lifespan. The good news: a thorough deep clean can restore freshness and performance. This guide walks you through science-backed cleaning techniques, preventive strategies, and real-world solutions to permanently eliminate that stubborn mildew smell.

Why Washing Machines Develop Mildew Smell

The root cause of foul odors in washing machines lies in trapped moisture and organic residue. Unlike older top-loading models, modern HE washers use less water and tighter seals to improve efficiency. While eco-friendly, these features inadvertently encourage damp environments where mold and mildew thrive. Common contributors include:

• Residual moisture: Water remains in gaskets, drain pumps, and hoses after cycles.
• Detergent buildup: Excess soap doesn’t fully rinse away, creating a sticky film.
• Lint and hair: Accumulates in filters and crevices, decomposing over time.
• Fabric softener: Coats internal parts, trapping moisture and debris.
• Closed-door habits: Keeping the lid or door shut prevents airflow and drying.

According to Dr. Lena Patel, a microbiologist specializing in household appliances, “The rubber door seal on front-loaders is one of the most contaminated surfaces in homes. It’s warm, dark, and frequently wet—ideal conditions for fungal growth.”

“Mildew isn’t just about smell—it can release spores into the air and onto clothes, potentially triggering allergies.” — Dr. Lena Patel, Microbiologist

Tip: Always leave the washer door and detergent drawer open after use to promote drying.

Step-by-Step Guide to Deep Clean Your Washing Machine Drum

A complete deep clean involves both mechanical scrubbing and chemical treatment to break down biofilm and kill microbes. Follow this detailed process every 1–3 months, depending on usage.

1. Clear the area: Remove any clothes, laundry pods, or loose items. Pull out the lint filter (if accessible) and clean it under running water.
2. Inspect the door seal (front-loaders): Wipe down the rubber gasket with a microfiber cloth. Check folds for black spots—this is mold. Use an old toothbrush dipped in vinegar to scrub affected areas.
3. Run a hot water cycle with cleaning agent: Choose one of the following options:
   • 4 cups of white vinegar
   • ½ cup of bleach (only if safe for your model; avoid mixing with vinegar)
   • 150g of oxygen-based bleach (e.g., OxiClean)
   • Commercial washing machine cleaner (e.g., Affresh, Tide Washing Machine Cleaner)
4. Add cleaning solution: Pour vinegar or cleaner directly into the drum—do not use the detergent dispenser, as buildup may block it.
5. Start the hottest, longest cycle: Select “Sanitize,” “Tub Clean,” or “Heavy Duty” mode. For top-loaders, ensure the tub fills sufficiently to circulate the solution.
6. Pause and soak (optional): After the cycle starts, pause it for 30–60 minutes to allow the solution to penetrate grime.
7. Scrub the interior: Once the cycle finishes, use a damp cloth to wipe the drum, agitator (if present), and around the rim. For stubborn residue, make a paste of baking soda and water and gently scrub.
8. Clean the detergent drawer: Remove the tray and soak it in warm vinegar water. Scrub with a brush, rinse, and reinsert.
9. Wipe external surfaces: Don’t forget the control panel, door glass, and exterior casing. Use a vinegar-dampened cloth.
10. Run a rinse cycle: Run one additional cycle with plain water to flush out any remaining cleaner or debris.

Post-Cleaning Maintenance Tips

After deep cleaning, prevent recurrence by adopting daily habits:

• Leave the door and detergent drawer open between uses.
• Use high-efficiency (HE) detergent in recommended amounts.
• Avoid overloading the machine—clothes need room to move and rinse properly.
• Wipe the door seal weekly with a dry cloth.
• Remove wet clothes within 30 minutes of cycle completion.

Choosing the Right Cleaning Agent: Pros and Cons

Not all cleaners work the same way. Understanding their strengths helps you pick the best option for your machine and household needs.

Cleaning Agent	Pros	Cons	Best For
White Vinegar	Natural, deodorizes, dissolves mineral deposits	Strong smell during cycle; may not kill all mold strains	Routine maintenance, sensitive households
Bleach (Sodium Hypochlorite)	Kills bacteria and mold effectively	Corrosive; unsafe for septic systems; cannot mix with vinegar	Severe mold infestations (use monthly max)
Oxygen-Based Bleach (OxiClean)	Gentle on parts, color-safe, breaks down organics	Less effective on heavy limescale	Regular deep cleans, HE machines
Commercial Washer Cleaners	Specially formulated, often include surfactants	More expensive; some contain fragrances	Those wanting convenience and brand-specific safety
Baking Soda + Vinegar	Eco-friendly, boosts scrubbing power	Reacts immediately—best used separately, not mixed in drum	Odor neutralizing and light scrubbing

Tip: Never mix bleach and vinegar—they produce toxic chlorine gas. Always run a water-only cycle between switching cleaners.

Real Example: How Sarah Fixed Her Front-Load Washer’s Persistent Smell

Sarah, a mother of two in Portland, noticed her towels had a sour smell despite using premium detergent. Her front-load Samsung washer emitted a damp, basement-like odor every time she opened the door. She tried wiping the seal and using scented dryer sheets, but the problem returned within days.

After researching, she followed a full deep-cleaning protocol: she removed the detergent drawer, cleaned the rubber gasket with vinegar and a toothbrush, then ran a 90°C cycle with 4 cups of white vinegar. During the cycle, she paused it mid-way to let the solution soak for 45 minutes. Afterward, she wiped the drum and ran a second rinse cycle with OxiClean.

The difference was immediate. Not only did the smell vanish, but her next load of laundry came out fresher than before. She now maintains her machine by leaving the door ajar and running a vinegar cycle every six weeks. “I wish I’d done this sooner,” she said. “It took less than two hours and saved me hundreds on a potential repair.”

Preventive Checklist: Keep Your Washer Fresh Between Cleans

To avoid future mildew issues, follow this simple monthly checklist:

• ✅ Wipe the door seal with a dry cloth weekly
• ✅ Leave the door and detergent drawer open when not in use
• ✅ Use only HE detergent and measure precisely
• ✅ Remove wet clothes promptly
• ✅ Clean the lint filter (if accessible) monthly
• ✅ Run a cleaning cycle every 1–3 months
• ✅ Avoid excessive fabric softener or dryer sheets
• ✅ Inspect hoses annually for cracks or leaks

Frequently Asked Questions

How often should I deep clean my washing machine?

For average households, deep clean every 1–3 months. High-use homes (large families, frequent laundry) should do it monthly. Top-loaders generally need cleaning less often than front-loaders due to better airflow.

Can I use apple cider vinegar instead of white vinegar?

No. Apple cider vinegar contains sugars and pigments that can leave residue or discolor internal parts. Stick to clear, distilled white vinegar (5% acidity) for best results.

Why does my washer still smell after cleaning?

If odor persists, check the drain pump filter—a common trap for debris. Also, inspect hoses behind the machine for standing water or mold. In rare cases, the internal drum may have biofilm that requires multiple treatments or professional service.

Final Thoughts: A Clean Washer Means Cleaner, Fresher Laundry

Eliminating mildew smell from your washing machine isn’t just about comfort—it’s about maintaining hygiene and protecting your investment. Modern washers are designed to be efficient, but without proper care, they become reservoirs for mold and bacteria. By understanding how mildew forms and applying consistent cleaning practices, you regain control over your laundry environment.

The steps outlined here—deep cleaning with effective agents, regular maintenance, and smart usage habits—are proven to restore freshness and extend appliance life. Whether you choose vinegar, oxygen bleach, or commercial products, consistency is key. A clean drum ensures your clothes come out truly clean, not just rinsed with yesterday’s residue.

💬 Ready to reclaim fresh-smelling laundry? Pick a day this week to deep clean your washing machine. Share your experience or tips in the comments—your insight could help someone else finally solve their smelly washer problem.