Installation and repair of air-conditioning apparatus; Installation and repair of air-conditioning systems; Installation and repair of heating, ventilating and air-conditioning systems; Installation of air-conditioning apparatus for use in clean rooms; Installation of heating, refrigerating, air-conditioning, drying, ventilating and dust extraction apparatus; Installation of heating, ventilation and air-conditioning systems; Installation, maintenance and repair of air-conditioning apparatus; Installation, maintenance and repair of air-conditioning systems; Installation, maintenance and repair of cooling and air-conditioning systems for temperature-controlled environments; Maintenance and repair of heating, refrigerating, air-conditioning, drying, ventilating and dust extraction apparatus; Provision of information relating to the repair or maintenance of air-conditioning apparatus; Repair and maintenance of heating, refrigerating, air-conditioning, drying, ventilating and dust extraction apparatus; Repair or maintenance of air-conditioning apparatus