• Frame made from high quality aluminum profiled.
• Blades are sealed with foam gasket at the bottom to avoid rattling noise and to provide air fight operation.
• Blades open full or to any angle depending on the air velocity. Blades stay in position of opening without fluctuating when there is constant air flow. Blades close quietly when the air flow stops.
• Designed to maintain constant pressure level inside pressurized rooms by relieving excess air when it exceeds the desired limit.
• Generally installed on diesel generator plant rooms ventilation system and exhaust ducting.
• Non-return dampers prevent unwanted airflows against the intended airflow direction when the system is not in operation.
• Maximum differential pressure: 100 Pa.
• Casing with U-channel connection suitable for rectangular ducts.
• Available in standard sizes and many intermediate sizes.
• Non-return damper with formed aluminum blades for normal requirements; blades are fitted with seals for sound attenuation.
• Non-return damper, duct connection without flange holes.
• Non-return damper, duct connection with flange holes.
• Maintenance-free as construction and materials are not subject to wear.
• Contamination should be removed as it may lead to corrosion and to increased closed blade air leakage.

Application

• Non-return damper for Installation into ductwork.
• Prevention of unwanted airflows against the intended airflow direction when the system is not in operation.
• Blades close automatically when the system is shut down.
• Maximum differential pressure 100 Pa.

Special characteristics

• Any intermediate sizes within the standard size range are available.
• operating temperature: -20-80 °C.
• Maximum differential pressure: 100 Pa.
• Non-return dampers are opened and closed by the airflow; no actuator is required.
• Non-return damper with formed aluminum blades for normal requirements; blades are fitted with seals for sound attenuation.

Nominal sizes

■B: 200, 400, 600, 800, 1000, 1200, 1400, 1600 mm (intermediate sizes: 2011599 mm in increments of 1 mm).

■H: 215, 315, 415, 515, 615,715, 815, 1015, 1215, 1415, 1615 mm. (intermediate sizes: 216-1614 mm, in increments of 1 mm).

■Any combination of B x H.

Quick sizing tables provide a good overview of the volume flow rates with an airflow velocity of 2.5 m/s. Intermediate values can be interpolated

Installation and commissioning

■Horizontal airflow: Vertical installation.

■Vertical airflow: Installation into ducts with an upward airflow; horizontal installation.

■Straight upstream section required (at least B H) on the positive pressure side of fans.

■ Ensure gradual start-up of fans to avoid Only for installation in internal spaces. sudden pressure increase.

■For external walls the damper should be combined with a Type WG-KUL external weather louver.