Whole house fans are used to replace or supplement central air conditioning when the air outside is cooler than the air inside, usually in the evening and morning. They work best in areas with hot summer days, cooler summer nights and low humidity. Once the temperature cools down outside, whole house fans allow you to open a few windows, turn the fan on and watch the temperature inside the home drop as hot air is pushed out through the attic and roof, and cooler air is drawn in through the windows. In addition, whole house fans generally use 10% of the energy required by a comparably sized central air conditioner. When used properly, they can help to reduce air conditioning bills substantially, including in spring and fall when the air conditioner may become unnecessary. Please visit Flex Your Power for additional information.
To estimate your potential to save energy and money by installing this product, please see the U.S. Department of Energy's Home Energy Saver calculator.