Which Direction Should a Ceiling Fan Turn?

Summer Cooling Effect

• Ceiling fans don't bring down the temperature of a room, they just make it feel that way from the wind-chill effect they create. Fan blades are pitched at an angle so that rotating the blades counterclockwise at medium or high speeds moves air. The resulting breeze evaporates moisture from the skin and makes people feel cooler. Standing directly below the fan, you should feel a cool wind when the fan is rotating correctly. Larger rooms may need more than one fan to stir the air enough so it covers the entire area.

Warmth Distribution in Winter

• A switch on most fans reverses the motor so the blades can turn clockwise in the winter, which effectively changes the configuration of how the blades slice through the air, causing the air to move differently. Running a fan in winter forces warm air that rose to the ceiling back down toward the lower levels of the room. In cold weather, the ceiling fan helps reduce the number of times a furnace cycles because the warm air that would have been wasted at ceiling level is brought to thermostat level. The thermostat senses warmth and the furnace stays off. With the fan rotating clockwise, air is circulated upward, then back down along the perimeter of the room. Fans should be run at low speeds in cold months to prevent any wind-chill effect.

Mild Weather Days

• Winter is the only time rotating ceiling fans clockwise makes sense. Mild weather may be too warm to feel comfortable but not hot enough to justify running the air conditioning system. A ceiling fan's breeze helps keep people feeling cool and at a far lower cost than using air conditioning.

Running Fans All Day

• In summer, ceiling fans need only be used when people are present in the room since the air temperature is unchanged with a fan running. Keeping the fan on when no one is present simply wastes electricity. But since ceiling fans do affect room temperatures in winter, fans may be kept running regardless of whether people are present.