closed water central heating and drinking water systems for residential and non-residential building use, consisting principally of expansion tanks, metal and plastic pipes, tubes, safety valves, float-valves, pressure and temperature meters, as well as brackets and supports therefor; expansion tanks for use in such central heating systems and drinking water installations, waterworks, domestic hot water installations, waterworks, domestic hot water supply, bathroom installations and plumbing installations; expansion tanks with exchangeable membranes for domestic and industrial use; compressor-controlled automatic expansion vessel storage units for domestic and industrial use; float-valves, air separation units, safety valves, pressure and temperature meters, clamps, rails, brackets, straps, supports, T-connectors, metal and plastic pipes, pipe connectors and joints, and tubes and cables all being component parts of any of the foregoing