Velocity Boiler Works (Crown) 233081 Flue Sensor Kit is an OEM replacement sensor designed for BWC070–120 and Model 151 condensing gas boilers. Installed in the flue passage, it monitors exhaust gas temperature and sends thermal feedback to the boiler control system, helping maintain safe operating conditions and prevent excessive temperatures. This sensor supports proper combustion c... https://www.partshnc.com/233081-velocity-boiler-works-crown-flue-sensor-kit-bwc070-120-151