The bringing together, for the benefit of others, of heating installations and steam generating installations, stoves being heating apparatus, boilers for central heating and natural gas installations, gas boilers, burners, heaters, heaters for baths, radiators, heat pumps, electric water boilers, solar collectors for heating and solar-energy-powered heating installations, heating apparatus for solid, liquid or gaseous fuels, cookers, steam, gas and fog generators, steam boilers, other than p...