Responsible for maintenance and repair on ventilation, air conditioning, and refrigeration equipment and systems. Work from blueprints, design specifications, and manufacturer instructions to install compressors, motors, condensers, thermostats, fans, ducts, pipes, and other mechanical, electrical, and electronic components into place. Use hand tools such as wrenches, electric drills, pipe cutters and benders, acetylene torches, and hammers to connect parts to duct work, gas and refrigerant lines, and other piping. Also use test instruments such as voltmeters, thermometers, and manometers. After attaching temperature and pressure control testing devices, charge the system with refrigerant, and then test it for proper operation, making any necessary final adjustments.