General Information
Application
- Non-return dampers for the fresh air and exhaust air ducts of ventilation and air conditioning systems
- 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: 20.07 in w.g.
Special features
- Robust, maintenance-free construction
- Maximum differential pressure: 20.07 in w.g.
- Closed blade air leakage with back pressure, in closing direction, to EN 1751, class 4
- Damper for negative or positive pressure (air extract or discharge)
- Operating temperature 32 to 176 °F
- Optional temperature resistant construction for up to 392 °F, with Viton seal
- Installation in horizontal or vertical ducts
- Maintenance-free DU bearings with Teflon coating, bearing shafts made of stainless steel
Nominal sizes
- B: 8, 16, 24, 32, 39, 47 in (intermediate sizes: 8 – 47 in, in increments of 0.04 in)
- H: 14, 27, 40, 53, 66, 79 (intermediate sizes 14 – 20, 27 – 33, 40 – 46, 53 – 59, 66 – 72 in increments of 0.04 in)
- Any combination of B × H
Variants
- ARK: Non-return damper with linked blades, preferably for variable volume flows
- ARK-1: Non-return damper with adjustable blade restrictors, preferably for constant volume flows
Construction
- Galvanised sheet steel, duct connection without flange holes
- A2: Stainless steel
- G: Duct connection with flange holes
Accessories
- Installation subframe for the fast and simple installation of mechanical self-powered dampers
Standards and guidelines
- Closed blade air leakage (against the intended airflow direction) to EN 1751, class 4
- Casing air leakage to EN 1751, class C
Maintenance
- 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
