How to Clean a Dehumidifier: Bucket, Filter and Coils
Quick answer
Unplug the dehumidifier first. Empty and wash the bucket weekly with warm water and mild dish soap (a white vinegar rinse removes slimy film), clean the air filter every 2 to 3 weeks by vacuuming or rinsing it and letting it dry fully, and gently brush or vacuum the coils and grilles each season. Flush the drain hose monthly if you use one. Always follow your manual for your model.
A dehumidifier pulls water out of damp air all day, which makes its bucket, filter and coils a magnet for dust, slime and mold. A dirty unit removes less moisture, uses more electricity and can start to smell musty itself. Cleaning takes about 15 minutes.
What you need
- Mild dish soap and warm water
- White vinegar (for film and odor in the bucket)
- A soft brush or old toothbrush
- A vacuum with a soft brush attachment
- A microfiber cloth
How to clean a dehumidifier, step by step
1. Unplug and empty it
Turn the unit off, unplug it and let it sit for a few minutes. Remove the bucket and pour the water down a drain.
2. Wash the bucket
Wash the bucket with warm, soapy water and a soft brush, paying attention to corners and the float. If there is slime or a musty smell, fill it with a mix of one part white vinegar to one part water, let it sit 15 to 30 minutes, then scrub and rinse. Dry it completely before putting it back. Do this weekly when the unit runs daily.
3. Clean the air filter
The filter is usually behind the front or rear grille. Pull it out and vacuum off the dust, then rinse it in lukewarm water if it is a washable mesh filter. Let it air dry completely; a damp filter can grow mold. Clean it every two to three weeks, or more often in dusty spaces. Some models have a filter-clean indicator light.
4. Wipe the grilles and housing
Wipe the outside, air intake and outlet grilles with a damp microfiber cloth. Never spray water into the unit.
5. Dust the coils (each season)
With the filter removed, you can see the metal coils and fins. Brush them very gently with a soft brush or vacuum brush attachment, moving in the direction of the fins so you don’t bend them. Dusty coils remove less moisture. If the coils are heavily soiled or iced, follow the manual or call for service.
6. Flush the drain hose
If you use continuous drainage, disconnect the hose monthly, flush it with warm water, and check it runs downhill all the way to the drain without kinks.
7. Reassemble and restart
Refit the dry filter and bucket, plug it in and set the humidity to around 45–50%.
Cleaning schedule
- Every time it’s full: empty the bucket.
- Weekly: wash the bucket.
- Every 2 to 3 weeks: clean the filter.
- Monthly: flush the drain hose.
- Each season, and before storage: full clean including the coils; store it clean and completely dry.
If your dehumidifier smells musty
A musty smell usually comes from a dirty bucket or filter, or from water that sat in the bucket for days. Clean both, use a vinegar rinse in the bucket, and empty it more often. If the smell remains, there may be mold inside the unit, which needs service. A dehumidifier that smells can’t fix a musty-smelling house.
Signs your dehumidifier needs attention
- The bucket fills more slowly than it used to, but the room still feels damp.
- Frost or ice on the coils (often because the room is too cold, or airflow is blocked by a dirty filter).
- Louder than normal, or the fan runs but no water collects.
If it still can’t keep up after cleaning, it may simply be too small for the space; see what size dehumidifier you need. To learn what your dehumidifier does and doesn’t do for air quality, read does a dehumidifier purify the air and the ideal indoor humidity level.
Frequently asked questions
Can I use bleach to clean a dehumidifier bucket?
Some manuals allow a weak bleach solution. Rinse thoroughly afterward and never mix bleach with vinegar. Soap and a vinegar rinse are usually enough.
Can I put the bucket in the dishwasher?
Only if the manual says so. Many buckets have a float or sensor that can be damaged by heat.
Is dehumidifier water safe to use?
Not for drinking or pets. It can contain dust, bacteria and metals from the coils. Some people use it for flushing toilets or watering non-edible plants.
How long do dehumidifiers last?
Often 5 to 10 years with regular cleaning. Clean filters and coils help the compressor last longer.