Dehumidifiers can accumulate rather nasty smells and odors. Dehumidifiers work to remove humidity, or evaporated water, from the air in much the same way an air conditioner does. This necessitates accumulating the condensation the dehumidifier generates and the unit holding water for potentially prolonged periods of time. If you are faced with a bad smell emanating from your dehumidifier, there are a few possible causes you should look into to relieve the problem.

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Mold growth in a dehumidifier can be a health hazard.

Standing Water

Empty your dehumidifier as often as possible. Dehumidifier water is a potential cauldron for mold and mildew growth, which can cause sulfurlike smells. Never leave water standing in the dehumidifier for longer than you need to, and make sure you empty the basin at least once per day.

Dirty Basin

The basin in the dehumidifier, even if frequently emptied, is perpetually wet or damp. This makes it an ideal place for mold, mildew and bacterial growth. Rinse your basin with a mild solution of detergent and water, or vinegar and water, to disinfect the plastic. Be sure to scrub out any accumulated algal growth, which may be present as a green or pink film on the plastic surface.

Coil Issues

Dehumidifiers take moisture from the air by blowing air across copper coils filled with cold coolant gas. Water accumulates on these coils because of the difference in temperature between the coils and the air. These coils are constantly damp, and can harbor similar organisms to those you might find in the basin. Unplug your unit and spray the coils down with a mild solution of vinegar and water. Never use bleach for cleaning these mechanisms, as it can damage delicate components.

Dirt and Dust on Fan Blades

The last part of your dehumidifier that may be harboring mold and mildew is the fan blades. Unplug your unit and remove the cage from around the fan. Wipe down the blades with a solution of soap and water, and remove any hair, dirt and debris caught in the area. Vacuum out the fan motor and the general area, then reattach the cage before plugging in the unit and testing to see if the sulfur smell persists.