The Danfoss 015G3098 Thermostatic Sensor, Mounted RAS-D, is a temperature-sensing component designed to regulate heating system performance by responding to changes in room temperature. It works with a thermostatic radiator valve, sensing ambient air temperature and adjusting the valve to control hot-water flow through the radiator. This sensor is commonly used with hydronic heating s... https://www.partshnc.com/danfoss-015g3098-ras-d-mounted-thermostatic-sensor