The Lochinvar & A.O. Smith 100208549 Inlet Water Sensor is a temperature-sensing component designed to monitor incoming water temperature in gas-fired HVAC systems. It works by transmitting accurate temperature readings to the control board, allowing precise regulation of heating operations. Visit The Website: https://www.partshnc.com/inlet-water-sensor-5 https://www.partshnc.com/inlet-water-sensor-5