Installation of heating, refrigerating, air-conditioning, drying, ventilating and dust extraction apparatus; Repair and maintenance of heating, refrigerating, air-conditioning, drying, ventilating and dust extraction apparatus; Maintenance and repair of heating, refrigerating, air-conditioning, drying, ventilating and dust extraction apparatus; Installation, maintenance and repair of heating, ventilation and air conditioning (HVAC) systems; Consultancy relating to the installation, maintenance and repair of heating, ventilation and air conditioning (HVAC) systems; HVAC contractor services; Installation of HVAC systems; HVAC duct cleaning services