A Whole House Fan is an environmentally-friendly, efficient way to cool your home. When the temperature cools in the evening, just open a few windows and turn on your Whole House Fan. The Whole House Fan will bring cool fresh air into your home while pushing the hot stale air into your attic and out the existing roof vents. We recommend running the unit for several hours in the evening and running it again in the morning. You will experience the immediate benefits of a Whole House Fan as a cool, refreshing breeze comes rushing through your home.