HVAC service technicians specialize in installing, maintaining, and repairing HVAC equipment, indoor air quality, and pneumatic control systems. Working conditions and responsibilities will vary every day. Duties include meeting with customers at their homes or business to perform customer-requested work orders, preventative maintenance checks, warranty services, and emergency repairs. They are responsible for troubleshooting, testing equipment, diagnosing, and fixing various HVAC system components, including air conditioners, furnaces, thermostats, compressors, boilers, and chillers. HVAC service technicians use a company truck to visit job sites.