Ceiling fans were the first home comfort appliance, appearing in residences around the turn of the 20th century as electrification spread across the country. Here in the 21st century, ceiling fans are more relevant than ever. A typical 3-ton central air conditioner consumes approximately 3,500 watts of electricity per hour. A ceiling fan with a high efficiency motor moves more than 5,000 cubic feet of air per minute at 170 rpm’s, yet uses less than 60 watts. As an adjunct to your A/C, it’s a low-cost efficiency and comfort booster in your strategy to lower home cooling costs.
Ceiling Fan Theory
A ceiling fan exploits the same wind-chill factor that makes a windy winter day feel more chilly than it actually is. By evaporating perspiration and increasing body heat loss, the gentle downdraft produced by the counter-clockwise rotation of a ceiling fan in summer increases the perception of coolness, allowing you to set the A/C thermostat higher without reducing comfort. For every degree you can nudge the thermostat up, you’ll save as much as 3 percent on cooling costs.
Sizing and Pitch
For optimum cooling performance and energy savings, a ceiling fan should be sized to the room’s square footage:
Up to 75 square feet = 29 to 36-inch fan
76 to 144 square feet = 36 to 42-inch fan
145 to 225 square feet = 44-inch fan
226 to 400 square feet = 50 to 54-inch fan.
Blade pitch affects the volume of air moved by a ceiling fan. The appropriate blade pitch is generally in the range of 12 degrees to 14 degrees. A lesser angle doesn’t move enough cubic feet of air per minute to produce an optimum chill effect, while a steeper angle may blow papers around and disturb occupants.
Remember that a ceiling fan only makes a room feel cooler to humans and pets. It doesn’t actually lower air temperature like an air conditioner. To avoid wasting energy, always turn ceiling fans off in unoccupied rooms.
For more info on the advantages of ceiling fans, contact the professionals at Brennan’s Heating & Air.