We have an opening for an HVAC Mechanic . You will perform specialized tasks in air conditioning, heating or ventilation and air conditioning/refrigeration (HVAC) controls maintenance, installation, and repair. This position is in the Infrastructure Maintenance and Utilities Department and may be located at LLNL main site (Site 200) or at Site 300 in Tracy, California. This position requires full-time on-site presence due to the nature of the work. You will  Perform fabrication, installation, alteration, troubleshooting, repair, operation, maintenance, adjustment and monitoring of a variety of air conditioning systems including large commercial and industrial chiller units and other associated HVAC/R components such as compressors, motors, variable air-volume, air handling units, ductwork, control systems (pneumatic, digital, and electronic) and equipment safety devices. Perform proper and safe handling of recovery, recycling, and reclamation of refrigerants in accordance with applicable policy and procedures. Perform routine journey level maintenance on heat exchangers and controls for heating domestic and industrial hot water. Inspect low pressure boiler systems and related heating equipment, assist in piping repair and installation, related to the HVAC system, including drain lines. Repair and/or replace pneumatic control lines and valves relating to pressure reducing stations, radiators, heating and cooling coil control valves, unit heaters, boiler control, and thermostatic controls. Provide testing, adjusting, and balancing services on air handling and hydronic systems in accordance with the National Environmental Balancing Bureau (NEBB) procedural standards for testing, adjusting, and balancing of environmental systems. Manage building conditions through the utilization of computerized energy/building management systems and equipment. Prepare standard reports including status reports, permit requirements, deficiency forms, and preventative work requests. Interact with technical, administrative, and craft personnel of all levels. Perform other duties as assigned.