To determine the proper setting for a dehumidifier, it is important to understand how it works. Dehumidifiers remove water vapor from the air to keep a room dry. A fan draws in and traps moist air from a room, and coils inside the humidifier work to cool down the air. This process causes the moisture in the air to condense into water droplets that the dehumidifier collects in a bucket or drain hose. Then, the dry air is released back into the room.

The humidity setting that you should select depends on the humidity level of the room where the dehumidifier is located. In rooms that have high levels of moisture and humidity, such as basements, a dehumidifier will help regulate the humidity level to prevent mold and other bacterial growth. To prevent mold growth and keep your home’s relative humidity at a comfortable level, it is recommended to aim for 30%-50% humidity in your home. Ideally, that should equate to a dehumidifier humidity setting of around 40%, but you may wish to adjust it up or down to find the humidity level that feels most comfortable for your space and your household.

To set the humidity level on a manually-controlled dehumidifier, locate the humidity control buttons or dial and set it to the desired level. It is important to ensure that the dehumidifier is placed in the right spot, with enough room for air to freely flow into and out of the dehumidifier. Most models release air through vents on the top, so leave some space around the dehumidifier so that the vents are not obstructed, keeping the unit at least a foot away from walls and furniture. It is also important to close all windows and doors to reduce humid air from entering your home, helping your dehumidifier work more efficiently.