The Karcher 4.580-360.0 Thermo Relief Valve Kit is a replacement component designed for use in compatible pressure washer systems. It works by automatically opening when water trapped inside the pump reaches a preset temperature, allowing hot water to discharge and cooler water to enter the system. This process helps reduce heat buildup during bypass operation and supports proper pump... https://www.wholetoolbox.com/karcher-4-580-360-0-thermo-relief-valve-kit