Multi Leaf Volume Control Damper – 630mm

It balances airflow in circular ducted systems. Multiple opposed blades give fine, progressive control of the air passing through the duct — fit one in each branch during commissioning and adjust it so every room or outlet receives its designed share of the air. Once set, the locking spindle holds the blade position so the system stays balanced in service.

The damper has spigotted ends for direct connection into spiral ducting of the matching diameter — a 200mm damper slides into 200mm spiral duct in the same way as any standard spiral component. Secure and seal the joints as you would the rest of the run, using duct sealant and appropriate fixings from our accessories range.

The range covers spiral duct diameters from 100mm up to 1000mm, including all the standard sizes between — 125, 150, 160, 180, 200, 224, 250, 315, 355, 400, 450, 500, 560, 600, 630, 710, 762, 800, 850, 900 and 950mm. Match the damper to the diameter of the duct run it will sit in; if your duct size is not listed, contact us and we will advise the nearest suitable option.

By hand, via a control spindle on the outside of the casing that locks the blades securely at the chosen position. The multi-blade opposed action gives finer, more progressive control than a simple single-blade damper, which makes accurate commissioning easier — particularly at partially closed positions where single blades tend to be coarse.

Both the case and the blades are galvanised steel, giving a robust, corrosion-resistant damper suited to commercial ductwork. If you need finer control on a rectangular duct, see our rectangular volume control dampers, which are made to order to your exact width and height with a choice of hand, spindle or actuator control.