How to Clean a Dehumidifier and Its Filter
Three parts need regular attention: the air filter, the water bucket, and the air intake and outlet. A clogged filter cuts airflow, and water standing in a bucket is where mold and mildew grow. The steps below follow a manufacturer's own manual; the intervals for your model may differ, so check yours.
Turn it off and unplug it
Every step below starts with the unit off and unplugged. Midea's manual also warns not to splash water directly onto the unit, because it can cause an electrical shock, damage the insulation or make the unit rust.
The cleaning routine in one manufacturer's manual
From Midea's manual for its Cube dehumidifier:
- Air filter, about every two weeks. Pull the filter out, wash it with clean water, let it dry, and put it back. The unit has a filter indicator light; on the Cube you reset it by holding the fan button for 3 seconds.
- Bucket, every few weeks. Partly fill it with clean water and a mild detergent, swish it around, empty and rinse. The manual gives the reason: to prevent the growth of mold, mildew and bacteria. Don't put the bucket in a dishwasher.
- Grille and case. Water and a mild detergent; no bleach or abrasives. Dust on the air intake and outlet comes off with a vacuum cleaner or a brush.
- Pump filter, on pump models. Remove it and rinse it with clean water, or clean the mesh with a soft brush or sponge.
Source: Midea, Cube dehumidifier user manual (MAD20S1QWT), read October 5, 2026. Other brands use different intervals and parts; your own manual wins.
Wash it or replace it?
It depends on the model. The Cube's air filter is washed, not replaced, according to its manual. Other models may use a filter sold as a replacement part. Look in the manual's care section or parts list before buying a "replacement filter": if the manual tells you to wash it, there is nothing to buy.
A filter light that comes on is a reminder, not a fault. Clean the filter, then reset the light the way the manual describes.
Putting it away for the season
Midea's manual for storing the unit for a long time:
- Let it rest for a full day so the system dries out.
- Clean the unit, the bucket and the air filter.
- Cover it and store it upright in a dry, well-ventilated place.
If the dehumidifier smells after cleaning
A unit that is clean but the room still smells musty means the source is in the room. Dehumidifier for mildew smell covers both cases, and musty smell in the basement covers finding the source. Running the unit with a drain hose means no water stands in the bucket at all.