Pre-Insulated Non-Return Damper
PA-NRD Pre-Insulated Non-Return Damper
The PA - NRD is a duct mounted device that is composed of a set of horizontally mounted blades that are normally closed and are free to rotate around their horizontal axis.
The PA - NRD can be used at the exit terminal of exhaust ducts and fans for low & medium pressure (minimum 25 Pa, maximum 500 Pa).
Certain pressure is usually required before the damper opens to expel the exhaust air, which ensures the elimination of back flow.
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