Iris Volume Control Damper Manual

• Iris VCD dampers act as ideal airflow regulators and measurement aids.
• The special Iris design allows for accurate control smooth and quiet air flow and reliable measuring results.
• For the best results the install in straight runs of ductwork. Spigots are fitted as standard with safe-seal rubber gaskets which will slip inside female spiral tube.
• Equipped with an adjustment scale and measuring connections and spanner/lever.
• Suitable for continuous use from -10C up to +80C

Description:

The Zest Iris Damper is an ideal airflow regulator and measuring device for circular ducts. Accurate control, smooth and quiet air flow and reliable measuring results are achieved by the special iris construction. An easily readable scale assists quick and simple adjustment with a standard 13mm spanner. In the fully open position, the Zest Iris Damper provides 100% free area with no control mechanism in the airstream allowing easy and effective cleaning of the ductwork system.

Use as a control damper:

The reducing orifice arrangement maintains a uniform airflow over the cross-section of the duct. Closure of the iris produces an accurate throttling of air volume with an even airflow pattern, resulting in low noise levels.

Use as a measuring device:

The Iris Damper can be used for measuring airflow rates by means of the orifice plate principle. The accurate control mechanism guarantees exact opening dimensions corresponding to the adjustment scale. Each damper is provided with manometer connections for measuring the differential pressure which then can be directly used to determine the airflow from the measurement scale on the damper casing. The result of the regulation is thus immediately available and any subsequent checks can be carried out very quickly. Each damper is calibrated individually giving accurate measurement results, the method error being as low as +5% dependent on mounting position within the ventilation system (see mounting distances).

Air Tightness:

The Zest Iris Duct Damper has a ‘through the case’ airtightness which meets the requirements of the Eurovent Class C.

Temperature:

The Zest Iris Duct Damper is suitable for continuous use from -10ºC up to +80ºC (if there is moisture in the air the damper may freeze but will not be damaged in this condition unless operated whilst frozen).

Installation:

For the best results, the Zest Iris Damper should be installed in straight runs of ductwork. The damper may be fixed to ducting with rivets or self-tapping screws. We recommend joints are sealed with Tectape XT or Tecseal sealant to ensure an airtight connection. Flexible ducting may be fixed to the damper using Tecfix banding or clips.

Size Range:

The Zest Iris Damper is available in a comprehensive range of sizes from 80mm to 500mm.

Construction:

The Zest Iris Damper is manufactured from hot-dipped galvanised steel sheet and equipped with an adjustment scale and measuring connections. The tamper-proof control knob is adjusted with the spanner provided (the 80mm dia. has a lockable lever). Spigots are fitted as standard with rubber gaskets.