Heating, air-conditioning, and refrigeration systems consist of many mechanical, electrical, and electronic components, including motors, compressors, pumps, fans, ducts, pipes, thermostats, and switches. In central heating systems, a furnace heats air that is distributed throughout the building by a system of metal or fiberglass ducts. Technicians must be able to maintain, diagnose, and correct problems throughout the entire system. They may adjust system controls to recommended settings and test the performance of the entire system using special tools and test equipment. The work involves installing ductwork, and installing and wiring environmental control systems.
Work is performed both indoors and outdoors in work spaces ranging from outside on scaffolding to crawl spaces inside walls. Work requires physical stamina with considerable bending, lifting, carrying, pushing, and pulling.
Courses include blueprint reading, mathematics, electrical code requirements, and safety and first aid practices.