How Long Do You Run A Whole House Fan

For best results, run your whole house fan for at least 10 minutes first thing in the morning to bring a cool breeze through the house and into the attic. This will expel any hot stale air buildup from the night before. Then, close windows, doors and the blinds on the sunny side of your home. Experiment with your fan and home openings to maximize both your comfort and the performance of your fan.

Do not run your whole house fan during the day unless the temperature outside is cooler than the house is inside, though you may want to run the fan during the day to push air out of the attic. To do so, direct airflow from either the basement or the shady side of the home.

​You will get better cooling results for the next day if you run your fan longer into the evening, though, running the fan too long may cause you to become cold. Set your fan timer accordingly. Your whole house fan may also be used in mild winter days to bring fresh, clean air into the home, expel indoor air pollutants, and moisture buildup in your attic.