*Belt drive motor with included 2-speed wall switch 10-year parts limited warranty; 5-year labor limited warranty Maximum house size for peak performance: 3000 sq. ft. *The GAF Master Flow 6000 CFM 30 in. Belt-Drive Deluxe Whole House Fan is a smart energy saver for any home in a climate where air conditioning costs are a concern. It allows you to beat the heat by forcing hot air out of your home through the attic space while bringing in cooler outside air through your windows and doors. The 1/3 HP permanent split-capacitor motor provides ample power for home ventilation and ensures long-lasting use, while a flip of the 2-speed wall switch offers both high and low settings. Adding a GAF Master Flow 12-hour timer (model WHT36, sold separately) enables you t.