The Viessmann 7828749 Flow Sensor is a genuine OEM component designed to monitor water flow in compatible heating systems. It detects water movement and sends a signal to the boiler control, helping regulate operation and respond to domestic hot water demand. This sensor is used with Viessmann Vitodens 100-W B1KA, WB1B, WB1C, and compatible CPK CombiPLUS systems. By providing reliable... https://www.partshnc.com/7828749-viessmann-flow-sensor-b1ka-cpk