General description The Caldera valve 3 roads Junkers Zwr24 8717204198 is designed for use in gas boilers, specifically the ZWR24 model. This valve plays a crucial role in the hydronic heating system, allowing for efficient distribution of hot water throughout the home. Technical specifications Model: ZWR24 Part number: 8717204198 Usage The boiler utilizes the hot water generated to distribute heat through a network of tubes, radiating warmth into various rooms. This can be achieved using either steel radiators in new constructions or traditional cast iron radiators.