Plumbing; Drain and sewer cleaning and rootering services; Drain cleaning services; Heating contractor services; Heating equipment installation; Heating equipment installation and repair; HVAC contractor services; HVAC duct cleaning services; Plumbing and gas and water installation; Plumbing contractor services; Plumbing installation advisory services; Plumbing maintenance advisory services; Plumbing repair advisory services; Plumbing services; Advisory services relating to the installation of heating and cooling apparatus; Installation and repair of showers; Installation of heating and cooling apparatus; Installation of heating equipment; Installation of heating systems; Installation of heating, refrigerating, air-conditioning, drying, ventilating and dust extraction apparatus; Installation of heating, ventilation and air-conditioning systems; Installation of HVAC systems; Installation of plumbing; Installation, maintenance and repair of air purifying apparatus; Installation, maintenance and repair of heating apparatus; Installation, maintenance and repair of heating systems; Installation, maintenance and repair of fire, smoke and heat alarms; Installation, maintenance and repair of fire, smoke and heat detectors; Installation, repair and maintenance of heating equipment; Maintenance and repair of air-conditioning apparatus; Maintenance and repair of heating apparatus; Maintenance and repair of heating installations; Maintenance and repair of heating, refrigerating, air-conditioning, drying, ventilating and dust extraction apparatus; Maintenance of plumbing; Maintenance of HVAC systems, plumbing installations, and refrigeration systems; Repair and installation services, namely, the installation of heating, cooling and environmental control systems primarily using solar energy, renewable energy resources and rainwater; Repair and maintenance of heating apparatus; Repair and maintenance of heating, refrigerating, air-conditioning, drying, ventilating and dust extraction apparatus; Repair of air conditioners; Repair of air filtering apparatus; Repair of air filters; Repair of air-conditioning apparatus; Repair of garbage disposals; Repair of heating apparatus; Repair of household appliances and of residential heating, plumbing, air conditioning, and electrical systems; Repair of non-electric cooking heaters; Repair or maintenance of gas water heaters