The model PRD-RD pressure regulating dampers are a single blade round barometric damper assembly constructed from 24 ga galvanized steel, with a counter balanced weighted arm. The barometric bypass damper is an economical way to manage airflow and relieve excess air volume and air pressure. Damper blade adjustment is achieved by off-setting the 1/4 in hex shaped arm, securing weight #1 towards the bottom of that arm and moving the extra weight(s) (optional) up or down the arm, until the desired operation is achieved. For field versatility, the hex shaped arm can be inserted into either side of the damper. Additional weights can be added if necessary. The blade shafts are 5/8 in round Thermotuff™ plastic on all diameters. The barometric bypass damper is installed in the duct-work on horizontal duct runs and should be mounted level. The PRD-RD damper can relieve pressure by returning the air back to the return air duct or by directing it into a non-critical conditioned area. A restricting hand damper can be installed downstream of the bypass damper, which allows the installer to set sufficient differential pressure across the bypass relief duct.
Ultra-Zone™ Pressure Regulating By-Pass Damper, Manual Barometric, Series: PRD-RD, 8 x 12 in Damper, Round, 24 ga, Single Blade, Steel, Galvanized, Domestic