# How to Get Rid of Dehumidifier Smell > A musty smell from your dehumidifier is almost always standing water in the tank or a dirty filter, not a fault in the unit. The cleaning steps that fix it, in order. Canonical: https://mizaanhome.com/en-ae/blog/dehumidifier-musty-smell-fix/ Last updated: 2026-07-29 --- A musty smell from a dehumidifier is, in most cases, caused by standing water in the tank, a dirty air filter, or moisture built up on the internal coil, not an actual fault in the unit. The first and most important fix is regular cleaning of the tank and filter, which solves the problem in most cases with no extra purchase needed. ## The quick answer **A bad dehumidifier smell is mainly caused by standing water in the tank, a dirty filter, or moisture on the internal coil, not a fault in the unit.** The first fix is cleaning: empty and wash the tank, clean the filter regularly, and let the unit air out after each use. If the smell persists after cleaning, dedicated tank cleaning tablets are a practical addition that helps dissolve buildup, but they complement cleaning rather than replace it. ## Key points - **The unit continuously collects water from the air by design**, which makes it an ideal environment for mold and bacteria to grow if it isn't cleaned regularly ([dehumidifier definition from ENERGY STAR](https://www.energystar.gov/products/dehumidifiers)). - **Standing water in the tank is the most common cause of the smell**, especially if the unit was left for a long stretch with water inside it and never emptied. - **A filter dirty with dust and moisture together is an ideal environment for mold** ([background on mold growth from US EPA](https://www.epa.gov/mold/brief-guide-mold-moisture-and-your-home)). - **Regular cleaning fixes the problem in most cases**, with no need for any extra purchase. - **The smell isn't a manufacturing flaw**, it's a natural result of built-up moisture and dust, like any appliance that collects water and air inside it. ## The real cause behind the smell A dehumidifier, by design, pulls in humid air and continuously collects the condensed water in a tank. That makes it an ideal environment for mold and bacteria to grow if it isn't cleaned regularly. The most common causes of the smell: - **Standing water in the tank** for a long stretch, especially if the unit was switched off with water still inside it. - **A dirty air filter** collecting dust and moisture together, an ideal combination for mold growth. - **Moisture built up on the internal coil** if the unit runs in a closed room without enough ventilation. - **A faint chemical smell on first use** is normal in some new units and fades with time, but if it turns into a persistent musty smell, the cause is moisture buildup, not the unit itself. ## Causes and quick fixes | Cause | Sign | Fix | |---|---|---| | Standing water in the tank | Musty or damp smell, especially after a period of disuse | Empty, wash, and dry the tank regularly | | Filter dirty with dust and moisture | Smell gets worse the more the unit runs | Wash or tap the filter clean per the manual | | Moisture on the internal coil | A faint damp smell even with a clean tank | Wipe visible moisture and improve ventilation around the unit | | Chemical smell on first use | A faint plastic smell that fades over time | Usually normal, keep an eye on it if it persists | ## The fix: cleaning steps in order 1. **Unplug the unit** before any cleaning step. 2. **Empty the tank and wash it** with warm water and mild soap, rinse well, and let it dry completely before reinstalling it. 3. **Remove the air filter and wash or tap it clean** per your model's manual, let it dry fully before putting it back, and if it's old or torn, replace it. 4. **Wipe any visible moisture on the internal coil** with a cloth from the outside only, without opening up the unit's internals yourself. 5. **Let the unit air out** somewhere well ventilated instead of a fully closed corner all the time. 6. **Repeat this cleaning on a regular schedule** (weekly, or per your model's manual), not only once the smell shows up. This routine fixes the problem in most cases with no need to buy anything extra. ## What if the smell persists after cleaning? If you've cleaned the unit with the steps above and a faint smell still lingers, there's a practical addition that can help: dedicated tank cleaning tablets dissolve mineral deposits and the biofilm buildup inside the tank more easily than water and soap alone. This addition complements cleaning, it doesn't replace it, so if your tank or filter is already genuinely dirty, tablets alone won't fix the root problem. Check your model's manual first to see if it supports this kind of cleaning, and if a strong smell persists despite regular cleaning, that's a sign it may be time to inspect the unit or replace it. ## A working example from our picks If you've decided your current unit genuinely needs replacing, a practical criterion worth looking for is a tank and filter that come apart easily for cleaning. An example from our shortlist: the **Pro Breeze 20L/Day Dehumidifier** (≈ 849 AED), with a tank and filter that come apart easily for regular cleaning, which is why it tops our [guide to the best dehumidifier in the UAE](/en-ae/best/best-dehumidifier/). Regular cleaning with the same steps above keeps its lifespan and smell in check just like any other unit. See the Pro Breeze 20L/Day Dehumidifier price on Amazon.ae ↗ ## Bottom line A bad dehumidifier smell is, in most cases, caused by standing water in the tank, a dirty filter, or moisture built up on the internal coil, not an actual fault. Regular cleaning (tank, filter, ventilation) fixes it in most cases with no extra purchase needed, and tank cleaning tablets, if your model supports them, are a practical addition, not a substitute for cleaning. If you want to understand where all this moisture in your home comes from in the first place, see [why is my house so humid in the UAE](/en-ae/blog/why-is-my-house-humid/), and if your issue is actually mold on walls or in closets rather than the unit's own smell, read [how to prevent mold in an apartment](/en-ae/blog/prevent-mold-in-apartment/). If your old unit genuinely needs replacing, head back to our [guide to the best dehumidifier in the UAE](/en-ae/best/best-dehumidifier/) or our [guide on how to choose a dehumidifier](/en-ae/guides/how-to-choose-a-dehumidifier/), and browse the full [dehumidifiers](/en-ae/dehumidifiers/) category. ## Sources - ENERGY STAR, "Dehumidifiers", definition of the dehumidifier and its internal parts like the tank, filter, and coil: https://www.energystar.gov/products/dehumidifiers - US EPA, "Mold, moisture and your home", background on mold growth in enclosed, humid environments: https://www.epa.gov/mold/brief-guide-mold-moisture-and-your-home ## Where to buy - [Pro Breeze 20L/Day Dehumidifier](https://www.amazon.ae/dp/B0C62J7S74/ref=nosim) --- > منهجية ميزان هوم: نعتمد على المواصفات الرسمية وإجماع تقييمات المشترين والأسعار المحلية، ولا نختبر المنتجات بأنفسنا (بلا ادعاء تجربة شخصية، وبلا تقييمات Review/AggregateRating من تأليفنا). الأسعار تقريبية ووقت النشر، وقد يحتوي الدليل على روابط تابعة. > > Mizaan Home method: we rely on official specifications, the consensus of buyer reviews, and local prices. We do not test products ourselves (no firsthand-testing claims, no self-authored Review/AggregateRating). Prices are approximate and correct at publication; this guide may contain affiliate links.