Model NPR-BI

Pressure Relief Door
Negative Pressure Relief - "Blow-In"

The NPR-BI pressure relief door is designed to open inward to prevent damage to ductwork and excessive negative pressure. The NPR-BI mounts vertically and must be properly secured and sealed to the ductwork by welding or with high pressure sealing cement and screws or rivets.

Standard Construction

Material: 12 ga. (2.8) galvanized steel.
Door Panel: 12 ga. (2.8) galvanized steel.
Hinge: Steel - continuous oiano type.
Gasket: 1/4" thick (6.4) comressible sealed neoprene.
Latch: Factory set at desired pressure [3.0 in. wg. to 8.0 in. wg. (0.8 kPa to 2.0 kPa)] - fine-tune adjustable in field.
Springs: Coiled, automatically return door to closed position when pressure is relieved.
Available Sizes: 24" x 10" (610 x 152)
                            24" x 12" (610 x 203)
                            18" x 18" (457 x 356)
                            24" x 24" (610 x 457)