This document specifies requirements and test methods for fittings and valves of factory made thermally insulated bonded twin pipe assemblies for hot water networks in accordance with EN 13941-1, comprising two steel service pipes, in most cases steel fittings and/or steel valves, steel components, polyurethane (PUR) foam thermal insulation and a casing of polyethylene. NOTE Steel components can be e.g. fixing bars. The twin pipe assembly can also include the following additional elements: Measuring wires, spacers and diffusion barriers. This document covers the following assemblies: fittings: bends, T-pieces and reducers; valves for main line. This document applies to fitting assemblies with a minimum design pressure of 1,6 MPa and valve assemblies with a minimum design pressure of 2,5 MPa.