For controlling variable and constant air flow rates in ventilation and air-conditioning installations.

The volumetric flow controller VAQS impresses with its simple design, high measuring precision and short design. The volumetric flow controller allows the volumetric flow in ducts to be kept constant or to be regulated using positive control Vmin, Vmax, “OPEN” or “CLOSED”. It can also be used as a room or duct pressure controller. In VAV systems the volumetric flow controller can regulate variable volumetric flows between Vmin and Vmax as a function of the supply air (room temperature controller). The volumetric flow setpoints Vmin and Vmax can also be altered at the controller at a later stage even after installation. The measuring crosses each comprising 6 measuring points, distributed in accordance with the median line method, enable a very accurate measurement of the air volume throughput.