Along with moisture, portable dehumidifiers are pulling in dust, mold spores, and other contaminants. An accumulation of these things can block the dehumidifier filter which hinders its ability to remove excess moisture from the air. Thus, sort of defeating its entire purpose and leading to potential issues, but these appliances only require a bit of routine maintenance. Cleaning a dehumidifier on a regular basis will take care of most problems.

How often should you clean your dehumidifier?

Give your dehumidifier a regular cleaning at least every few weeks during periods of heavy use and every month if it's used intermittently. A good rule of thumb is that the more frequently you empty the water collection bucket, the more frequently it needs to be cleaned. This debris can clog the air filter, decreasing proper airflow, thus making it harder to draw in moisture. The dark, wet environment plus a dirty filter are the perfect spot for mold growth and bacterial growth.

You'll know your dehumidifier needs a deep cleaning if:

  • there's an increase in noise level
  • if the water level isn't increasing (or the humidity level read-out isn't decreasing)
  • if there is a musty odor emanating from the unit
  • if there are visible signs of mildew buildup or mold growth
  • if the air filter has excessive dust buildup
Dusty surfaces on a basement dehumidifier.
Dust can affect the functionality of your dehumidifier. Credit: Emily Fazio

1. Prepare the Dehumidifier for Cleaning

  • Unplug the dehumidifier from the power source to prevent electric shocks.
  • Move the unit to a well-ventilated area.
  • If applicable, empty the water reservoir to prevent spills during the cleaning process.

Cleaning tools you'll need:

  • warm water
  • Mild detergent or mild dish soap
  • white vinegar
  • Soft bristle brush
  • Vacuum with a brush attachment
  • Clean, dry towel or microfiber cloth

2. Clean the Exterior Surfaces

  • Dampen a soft cloth with a mixture of mild detergent and water.
  • Gently wipe down the exterior surfaces and clean components of the dehumidifier to remove accumulation of dust, dirt, and any other debris.
  • Pay attention to any grime or buildup of dirt around the controls, vents, and seams.

3. Clean the Dehumidifier Bucket

  • Remove the reservoir bucket (water tank) from the dehumidifier (if applicable, check the manual for guidance).
  • Wash the water bucket with warm, soapy water, using a soft-bristled brush or damp cloth to scrub away any residue.
  • Rinse the dehumidifier tank thoroughly with clean water and allow it to air dry completely before reinserting the dry tank into the unit.

4. Clean the Filter

  • Refer to the manufacturer's instructions or user manual for accessing and removing the dehumidifier filter.
  • Gently vacuum the filter using a brush attachment to remove any dust particles, dirt, or stubborn debris.
  • If the filter is washable, rinse the filter clean under warm water and let the clean filter dry completely before reinstalling it. If not, replace the filter with a new one according to the manufacturer's recommendations.
Dirty, dusty filter on a dehumidifier.
Clean the air filters to promote good airflow. Credit: Emily Fazio

5. Clean the Coils and Internal Components

  • Carefully clean any visible dust or debris from the dehumidifier coils and interior components using a soft brush or soft cloth.
  • Use a vacuum cleaner with a brush attachment to remove any stubborn dirt or buildup.
  • If there are any areas with mold or mildew growth, clean them thoroughly with a mixture of white vinegar and water or a mild detergent solution.
  • Use a dry cloth or let the dehumidifier components air dry.

6. Reassemble the Dehumidifier

  • Once you get the components clean and dry, reassemble the dehumidifier according to the manufacturer's instructions.
  • Ensure that the clean bucket is securely in place and that all filters and panels are properly installed.

7. Test the Dehumidifier

  • Plug the dehumidifier back into the power source.
  • Turn on the unit and let it run for a few minutes to ensure that it's operating correctly.
  • Monitor the dehumidifier for any unusual noises or issues that may indicate further maintenance is required.

A basement living room with rolling cabinets and a dehumidifier.
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How can you prevent mold in a dehumidifier?

Mold spores occur naturally in the air. Some damp environments and certain times of the year see more of it than others. To prevent your dehumidifier from becoming a mold breeding ground: 

  • regular maintenance is crucial. Cleaning every couple of weeks.
  • For optimal performance, keep the area uncluttered and well-ventilated to optimize air flow.
  • Consider investing in an air purifier or air duct cleaning if indoor air quality is poor.
  • Don't pack away a dirty dehumidifier, be sure to clean the water collection tank and bucket filter and let them dry completely for storage.