Which Way Should Ceiling Fans Turn During Summer?

Hot Air

• Hot air rises. That's the physics principle you should remember even in the summer. In the winter hot air collects at your ceiling, so the logical thought would be to have the blades turn in the direction that best circulates that hot air throughout your room. Forcing the air upward helps maintain even heat at your living height without a breeze. You might assume that the opposite would hold true in summer but that is not always the case.

Perception or Reality?

• Human skin reacts to the circulation of air upon it. A breeze helps you feel cooler because it travels across your skin, gently evaporating moisture on the surface. Merely watching a fan rotate and feeling the air circulate causes you to perceive that you are cooler. Your perception can often be more heightened than the real circulation of air as it travels across your skin. This concept would lead you to decide the blades should rotate in such a manner to push the air downward so you can feel the air move.

Fan Location

• Consider the location of your fan when thinking about blade rotation. If your fan is high overhead, for example, at the top of a foyer, you might choose to rotate the blades to help direct the hot air up, relieving the stress on your air conditioner to repeatedly lower the temperature of the air on the lower level.

Summary

• Your heat pump or air conditioner instructions might direct you to set your fan in one direction or the other for optimal cooling effectiveness. Set the blades to rotate in the direction that makes you feel cooler. Even if that feeling is only perceived, the perception is your reality when it is hot. You want a ceiling fan to cool you off.