The best time to run a whole house fan is during periods when the outside air is cooler than the inside air, typically in the evening, at night or early morning. This is most common in climates where the temperature drops significantly after sunset.
Here are some specific recommendations on the best time to run a whole house fan:
Evening, Night, and Morning: Start running the whole house fan in the early evening when the outside temperature starts to drop. Continue running it throughout the night, and turn it off in the morning when the outside air starts to warm up.
Warmer Months: Use the fan during the warmer months of the year, when the outside air is more likely to be cooler than the inside air.
Open Windows and Doors: Make sure the windows and doors are open in the rooms you want to cool when you’re running the whole house fan.
Monitor Temperature: Keep an eye on the indoor and outdoor temperatures. If the outside air becomes warmer than the inside air, it’s time to turn off the fan.
Use in Conjunction with AC: In some climates, a whole house fan can be used to complement air conditioning. You can use the fan to cool down your home in the evening and at night, and then close up the house during the day and use the AC if needed.
Remember that whole house fans work most effectively in climates where there is a significant temperature difference between day and night. In hot and humid climates, they may be less effective and may even increase indoor humidity levels. Always ensure proper ventilation in your home.