li>Performs more complex repairs and maintenance duties, including, but not limited to: Tears-down and rebuilds water pumps, medical gas pumps and compressors, vacuum systems, and air compressors; Replaces and tests circuit boards for variable frequency drives; Repairs electrical control circuits; Replaces electrical components, such as motors, relays and electronic circuit boards; Welds various types of metals using appropriate welding methods (including TIG, MIG and Stick), if properly trained; Performs predictive maintenance (infrared scans, ultrasonic testing and laser alignment) on major plant equipment; Assists with performing maintenance on autoclaves and other process equipment. Under the general supervision of a Maintenance Supervisor, installs, modifies, troubleshoots, repairs, adjusts, calibrates, tests, operates and maintains chilled water, steam, condensate, domestic and heating water, medical gas, fire protection, computerized tube and DI water systems, the hospital's medical infectious waste incinerators and mechanical equipment such as pumps, motors, gearboxes, fans, air handling units, variable frequency drives and air compressors.