37 installation, repair, maintenance, retrofitting and modernization of apparatus and installations for heating, cooling, steam generating, drying, ventilation, air conditioning, air purification, heat recovery, humidifying and dehumidifying; installation, assembly, repair, maintenance, remote maintenance and cleaning of home automation apparatus and installations, burners, electrical apparatus, heaters, air conditioning installations, ventilation installations, refrigerating apparatus, heat pumps, installation of electricity generation, equipment for producing hot water, machines, fuel cells, cogeneration plants, pumps, water treatment apparatus, solar installations, photovoltaic installations as well as the parts, accessories and components thereof; providing advice with respect to installing, repairing and servicing of heating, ventilation and cooling apparatus; providing information with respect to installing, repairing and servicing of heating, ventilation and cooling apparatus