Fantech® dryer booster fans have been specially designed to solve the problems caused by long duct runs on clothes dryers. According to dryer manufacturers and some local building codes, booster fans should be added in the dryer duct run when the length of the duct exceeds 24 ft with no bends, 20 ft with one bend or 15 ft with two bends. When the dryer is on, Fantech®'s patented pressure sensing switch automatically turns the booster fan on. The warm, moist air in the dryer duct is exhausted out of the building quickly. The dryer booster fan monitors the status of the dryer and will turn itself off when the dryer stops. Wall-mounted indicator panel with LED display lets homeowners know that the fan is functioning properly.