Siemens Building Technology 257 02042 Valve Assembly 340155 7026 Smith 100167824 Control Board is Smith 100167824 Control Board is a critical integrated component designed for high efficiency Knight XL heating boilers Constructed from heavy duty ASTM B584 bronze with a high temperature silicone seat this Siemens Building Technology component is the professional choice for contractors seeking direct replacement valve assemblies that eliminate compatibility risks and ensure long term system stability engineered for high performance fluid regulation in hot or chilled water applications such as convectors and fan coil units