LK 551 HydroMix is an asymmetrical mixing valve for domestic hot water and heating systems. The mixing valve has a thermostatic element that regulates the supply of cold and hot water in order to achieve the desired temperature. The valve has an anti-scald function that shuts off the incoming hot water flow in case of failure of cold water supply. The product range includes thermostatic mixing valves with female threaded connections in sizes ½″–1″, male threaded connections in sizes ½″–1¼″, and compression fitting connections in 15 mm and 22 mm. All product variants within these connection types and dimensions are covered by this EPD. Article 181454, the best-selling product within the range, was selected as the reference product. The material composition, manufacturing processes and environmental performance of the reference product are representative of the entire product range covered by this EPD.