The Helios Fans WHR 200 is a compact water heater battery designed for connection to circular duct systems. Its robust casing is made from galvanised steel, and both spigots feature double lip rubber seals to ensure a secure fit with standard nominal ducts. The internal heating elements consist of copper pipes with aluminium fins, providing efficient heat transfer. With a maximum operating temperature of 100 °C and a pressure limit of 8 bar, the unit is suitable for demanding HVAC applications. For easy installation and maintenance, two inspection caps are located on the water connection side.