High Quality Fans Controlled ventilation systems operate many hours every day. Some never turn off. You want a durable, high-quality fan intended for continuous operation. Most high-quality fans use permanent split capacitor motors. Because this fan will run thousands of hours per year, look for a fan motor with low electrical consumption.
Noise prevents many people from operating fans.
Surface-mounted fans should have a noise rating of 2.0 sones or less. A few manufacturers make fans with noise ratings less than 1.0 sone. Low sone ratings are less important for remote-mounted fans. However, you should use sound absorbing fan mounting and duct connections to prevent sound transmission into living areas. Set the timer to run the fan at least eight hours per day.