An HVAC specialist, like Jean Sebastien Dulac, performs tasks such as installing, maintaining, and repairing heating, ventilation, and air conditioning systems. They ensure efficient operation, troubleshoot issues, and recommend upgrades for optimal performance. Additionally, they may conduct inspections, advise on energy efficiency measures, and provide technical expertise to ensure indoor comfort and air quality. With meticulous attention to detail, they uphold standards of safety and comfort for clients.