Old Number SPRD12

Single blade, steel barometric damper used to bypass excess air when majority of zone dampers are closed

Counter balanced weighted arm to control bypass air for zoned systems

Air pressure in duct system increases as zone dampers close, pushing the SPRD open automatically

Arm and weight both adjustable to control amount of air bypassed - Recommended for low pressure systems with less than 0.5 in. wc

For larger systems and tighter pressure control, use MARD damper and static pressure controller (SPC)