Furnish and install Johnson Controls RP-2000 Pressure Relief Backdraft dampers, which can be used for vertical or horizontal applications.
Shroud is to be constructed of 20-gauge galvanized sheet steel with integral rolled blade stop. The shroud shall include rolled stiffener beads to allow easy sealing to spiral duct work joints.
Blades are to be constructed of 0.016 inch thick aluminum with closing spring to ensure a tight seal and minimize back flow through the damper. Seals are to be vinyl foam pressed onto the blade. The blade hinge shall be designed with no frame penetrations, which would allow air leakage out of the duct.
Performance shall be designed for tight shutoff and tested in accordance with AMCA Standard 500. Leakage resistance for a 6-inch damper shall not exceed 8.7 cfm per square foot at a 1-inch pressure differential. The damper must be rated to operate over a temperature range of -40 to 200°F (-40 to 93°C) standard.
There shall be a spring adjustment to allow for field setting of pressure to open the damper.
Sizing shall be determined by the designer in accordance with accepted industry practices to ensure proper system performance.