Do Ceiling Fans Help With High Humidity?

Ceiling fans do not actually remove humidity from a room, but they do help keep people feeling more comfortable because fans help circulate air around the room.

Fan Design

Well-placed ceiling fans help people feel cooler in warm weather.Well-placed ceiling fans help people feel cooler in warm weather.
Air conditioning systems remove humidity, but the cost of running them is much higher. Ceiling fans use about the same amount of electricity as it takes to power a 100-watt light bulb.

The blades on a ceiling fan are set at an angle so that they can push air more effectively as they rotate. Fans typically include switches that vary the speed the blades turn: low, medium or high. In summer or on warm days with high humidity, fans need to run at a medium or high speed to achieve the best cooling effect. Fan size also determines the proper cooling for the room. If the room's longest wall is 12 feet or less, a 36-inch diameter fan will keep occupants feeling cool. Rooms with walls of 12 to 15 feet need a 42-inch fan and rooms 15- to 18-feet long should be equipped with a 52-inch fan.

Wind Chill Effect

While the room's actual temperature will not change on humid days, the breeze ceiling fans stir make the room seem that way. The breeze creates a wind chill effect that evaporates moisture from skin. Consequently, people feel cooler. "Just the air movement in the room alone can make it feel cooler by four degrees or more," the California Energy Commission claims.

Fan Rotation

Most ceiling fans have a switch that controls the direction the blades rotate. In summer, to achieve the wind-chill effect, blades must turn in a counterclockwise rotation. When set correctly at the proper rotation and fan speed, a cool breeze is evident when standing directly below the fan. Air continues to move and circulate throughout the room, but the strongest wind chill is apparent from the downdraft caused by the ceiling fan.

Running Fans Continuously

Since the room's temperature is not lowered by ceiling fans, the units should be turned off when people are not occupying the space. Running fans continuously when people are not present wastes electricity and may raise temperatures slightly as the heat from fan motors permeate the room.

About the Author

Robert Korpella has been writing professionally since 2000. He is a certified Master Naturalist, regularly monitors stream water quality and is the editor of freshare.net, a site exploring the Ozarks outdoors. Korpella's work has appeared in a variety of publications. He holds a bachelor's degree from the University of Arkansas.