Hauck Butterfly Valves control the flow of low-pressure combustion air or fuel gas to burner systems. Two versions of the valve are available; the BVA series for ambient services and most fuel gases; and the BVA-H series for preheated air applications up to 425ºC. The valves are ideal for an individual burner or zone control and can be used as a trim valve to balance individual burners. Hauck BVA valves utilize maximum port openings for high flow rates. An easily read dial plate helps the operator maintain settings from burner to burner. Settings can be easily duplicated allowing a quick return to previous flow rates. The BVA is available in both automatic and manual control models. The manual 100 series valves are equipped with a short control lever and a thumbscrew to easily set and lock valve position. The automatic 400 series valves come with tapped and threaded bolt locations for the addition of a control motor.