Wage and Hour Division (WHD)
Service Contract Act Directory of Occupations
23400 Heating, Refrigeration And Air-Conditioning Mechanic
Installs, services and repairs environmental-control systems in residences, department stores, office buildings and other commercial establishments, utilizing knowledge of refrigeration theory, pipefitting and structural layout. Mounts compressor and condenser units on platform or floor, using hand tools, following blueprints or engineering specifications. Fabricates, assembles and installs ductwork and chassis parts, using portable metalworking tools and welding equipment. Installs evaporator unit in chassis or in air-duct system, using hand tools. Cuts and bends tubing to correct length and shape, using cutting and bending equipment and tools. Cuts and threads pipe, using machine-threading or hand-threading equipment. Joins tubing or pipes to various refrigerating units by means of sleeves, couplings or unions, and solders joints, using torch, forming complete circuit for refrigerant. Installs expansion and discharge valves in circuit. Connects motors, compressors, temperature controls, humidity controls and circulating ventilation fans to control panels and connects control panels to power source. Installs air and water filters in completed installation. Injects small amount of refrigerant into compressor to test systems and adds freon gas to build up prescribed operating pressure. Observes pressure and vacuum gauges and adjusts controls to insure proper operation. Tests joints and connections for gas leaks, using gauges or soap-and-water solution. Wraps pipes in insulation batting and secures them in place with cement or wire bands. Replaces defective breaker controls, thermostats, switches, fuses and electrical wiring to repair installed units, using electrician's hand tools and test equipment. May install, repair and service air conditioners, ranging from fifteen to twenty tons cooling capacity, in warehouses and small factory buildings.