Pressure Relief Dampers

Backdraft dampers with adjustable start-open pressure.

Pressure relief dampers are backdraft air dampers with an adjustable start-open pressure. This provides the capability of maintaining a relative constant pressure at various airflows. The damper closes when there is a decrease in differential pressure. This damper is generally used as a safety or controlling device. For example, mounting this damper on a duct section would relieve unexpected overpressure or relieve negative pressure downstream of a rapidly closing fire damper.

HPR-120

2V blades; pressure relief 0.1 to 1 in. wg (.025 - .249 kPa); back pressure of 5 to 8½ in. wg (1.24 - 2.11 kPa); velocity up to 5150 fpm (26.2 m/s) and temperatures from -20°F to 250°F (-29°C to 121°C)

VIEW HPR-120

HPR-230

Fabricated airfoil blades; pressure relief ¼ to 4 in. wg (.06 kPa to 1 kPa); back pressure of 6 to 13½ in. wg (1.5 to 3.4 kPa); velocity up to 5150 fpm (26.2 m/s) and temperatures from -40°F to 250°F (-40°C to 121°C).

VIEW HPR-230

HPR-330

Fabricated airfoil blades; pressure relief ½ to 6 in. wg (.012 - 1.5 kPa); back pressure of 13½ to 20 in. wg (3.4 - 5 kPa); velocity up to 6400 fpm (32.5 m/s) and temperatures from -40°F to 250°F (-40 to 121°C).

VIEW HPR-330