Whole House Fan Mounting Location Ceiling Quiet Design Yes Number of Speeds 2 Nameplate Voltage 120V AC Speed Controllable Yes Blade Diameter 24 in Drive Type Direct Drive Maximum Airflow 6 878 cfm Maximum Noise Level 1.8 sones Wattage 727 W Coverage Area 3 439 sq ft Rough Opening Type Square For High-Static Pressure Applications Yes High-Efficiency Motor Yes Number of Blades 3 Blade Material Steel Housing Material Steel Grille Material Aluminum Standards UL Listed