The Young Regulator Model 3100-Box is an exhaust air automatic damper that opens and closes by the operation of the room light switch, a motion detector, or some other control. It consists of a rectangular, opposed-blade damper behind the grill with a round discharge outlet.
Unlike traditional constant volume exhaust systems, the quantity of air being exhausted from the building is dynamic, determined by the number of automatic dampers that are open. The Young Regulator 3100BOX operates only when switched on. When in is not being used, there is minimal air leaving the space.
For relief a bypass loop of outdoor air can be installed. Optionally a variable speed fan or motor VFD could be used.