Quick answer
A mildew smell in your dishwasher is usually caused by trapped moisture or food particles. Clean the filter, check the drain, and run a vinegar cycle to eliminate the odor.
Confirm the symptom
- Smell is musty or moldy
- Odor is strongest after a wash cycle
- Dishes smell bad after washing
- Smell comes from the bottom of the dishwasher
Tools and prep
- Rubber gloves
- White vinegar
- Baking soda
- Soft brush or sponge
- Microfiber cloth
- Plastic scraper
- Dishwasher-safe disinfectant
- Owner's manual
- Screwdriver (if needed for filter access)
Step-by-step troubleshooting
- Turn Off Power and WaterDo: Unplug the dishwasher or turn off the circuit breaker. Shut off the water supply valve.Observe: Dishwasher is powered down and water is off.Means: Ensures safety during cleaning.Next: Clean the filter
- Clean the FilterDo: Locate the filter at the bottom of the dishwasher. Remove it and rinse under running water. Use a soft brush to scrub away debris.Observe: Filter is free of food particles and debris.Means: Clogged filters can trap moisture and cause mildew.Next: Check the drain
- Check the DrainDo: Look at the drain area for standing water or clogs. Use a plastic scraper to remove any buildup.Observe: Drain is clear and dry.Means: Standing water promotes mildew growth.Next: Clean the interior
- Clean the InteriorDo: Wipe down the interior with a mixture of white vinegar and water. Use a microfiber cloth to remove any residue.Observe: Interior is clean and dry.Means: Vinegar helps eliminate mildew and odors.Next: Run a vinegar cycle
- Run a Vinegar CycleDo: Place a cup of white vinegar in a dishwasher-safe container on the top rack. Run a hot water cycle without dishes.Observe: Vinegar neutralizes odors and mildew.Means: Vinegar helps sanitize and deodorize the dishwasher.Next: Check for lingering odor
- Check for Lingering OdorDo: After the cycle, open the dishwasher and check if the odor is gone.Observe: No lingering mildew smell.Means: The odor has been successfully eliminated.Next: Finish
Common causes
| Cause | Likelihood | Difficulty | Part often needed |
|---|---|---|---|
| Clogged Filter Trapped food particles and moisture create a breeding ground for mildew. | Common | Easy | Dishwasher filter |
| Standing Water in Drain Water trapped in the drain promotes mildew growth. | Common | Easy | Drain pump |
| Poor Ventilation Inadequate air circulation after a cycle can cause moisture buildup. | Sometimes | Medium | Ventilation system |
| Food Residue on Dishes Leftover food particles can decompose and cause mildew. | Sometimes | Easy | Dishwasher detergent |
| Blocked Air Gap An air gap prevents backflow but can become clogged, leading to mildew. | Rare | Medium | Air gap |
| Faulty Door Seal A damaged door seal can allow moisture to escape and cause mildew. | Rare | Medium | Door seal |
Parts matching
Common parts that may be needed to fix a mildew smell in your dishwasher:
- Dishwasher filter
- Drain pump
- Air gap
- Door seal
- Ventilation system
- Dishwasher detergent
Always use parts recommended by your dishwasher's manufacturer for compatibility and safety.
When to call a professional
- The smell persists after multiple cleaning attempts
- You notice visible mold or mildew inside the dishwasher
- The dishwasher is making unusual noises or not draining properly
- Standing water remains in the bottom after a cycle
- The door seal is damaged and cannot be replaced easily
- You suspect a deeper issue with the drain pump or ventilation system
FAQ
Can I use bleach to clean my dishwasher?
Avoid using bleach as it can damage the dishwasher's interior and leave harmful residues. Use vinegar or a dishwasher-safe disinfectant instead.
How often should I clean my dishwasher filter?
Clean the filter at least once a month to prevent clogs and mildew buildup.
Why does my dishwasher smell even after cleaning?
Persistent odors may indicate a deeper issue like a faulty drain pump or blocked air gap. Check these components or call a professional.
Can hard water cause a mildew smell?
Hard water can leave mineral deposits that trap moisture and promote mildew. Use a water softener or dishwasher-specific cleaner to address this.
Is it normal for my dishwasher to smell after a cycle?
A slight odor is normal, but a strong mildew smell indicates a problem that needs attention.