Dehumidifiers reduce indoor humidity in areas prone to high humidity conditions. Excessive humidity can cause mold, mildew and an increase in other potential allergens. Additionally, humidity can make the indoor temperature feel hotter than it is. Dehumidifiers are useful home appliances but are not without their share of dangers if not maintained properly.

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Humid conditions can be a breeding ground for mold and mildew.

Compressed Coolant

Dehumidifiers contain compressed coolant, typically Freon. These gasses are potentially hazardous to your health and the environment. A closed system contains them when the unit is functioning properly, but they can escape if the unit has damage or a leak. The coolant is under high pressure, and only an authorized service technician should tamper with or repair the coils of the unit.

Fire Hazard

As with any other electrical appliance in your home, dehumidifiers bring the risk of fire. They have numerous moving parts that generate significant amounts of heat, including motors, compressors and condensers. Additionally, homeowners may feel more comfortable leaving a dehumidifier running while they are out of the house, as compared to an electric stove or heater, which can further increase the fire hazard.

Mold and Mildew

A dehumidifier that runs constantly has numerous parts that are consistently damp and warm. This is a breeding ground for mold, mildew and fungal spores. If you don't properly clean and disinfect a dehumidifier, it can potentially grow and spread the mold and mildew throughout your home. Wash the unit's water collection basin with a mild detergent regularly, and wipe the coils down with soap and water as indicated by the user manual that came with the unit.

Safety

While they introduce some risks, dehumidifiers are no more dangerous than most other home appliances. They have some specific maintenance requirements owing to their function, but they are perfectly safe when maintained. In fact, they can improve indoor air quality by keeping humidity down and thereby decreasing the likelihood of mold growth. Additionally, they can assist home air conditioning systems when used in especially humid rooms, such as laundry rooms and basements.