Refrigeration Engineer: Alternate titles: cooling-system operator; operating engineer; stationary engineer, refrigeration. Operates freon, carbon-dioxide, or ammonia gas-cooling systems to refrigerate rooms in establishments, such as slaughtering and meat packing plants and dairies, to air-condition buildings, or to provide refrigeration for industrial processes: Opens valves on equipment, such as compressors, pumps, and condensers to prepare system for operation and starts equipment and auxiliary machinery. Observes temperature, pressure and ampere readings for system and equipment and adjusts controls or overrides automatic controls to obtain specified operation of equipment. Records temperature, pressure, and other readings on log sheet at specified intervals. Measures density of brine, using hydrometer, and adds calcium chloride to lower temperature to specified degree. Connects hose from supply tank to compressor to replace coolant. Makes periodic inspection of equipment and system to observe operating condition and need for repair or adjustment. Adjusts controls to isolate and clear broken lines for repair or shuts down equipment. May repack pumps and compressors, clean condensers, and replace worn or defective parts using hand and power tools. When operating refrigeration or air-conditioning equipment aboard ship, may be known as Reefer Engineer (water trans.) and must have endorsement on Merchant Mariner's document as Refrigerating Engineer.