This is a “Unistat 620w” undergoing the final part of its Factory Acceptance Test (FAT). Cycling between 20°C and -60°C, we are also monitoring and recording temperatures, pressures at various points around the unit as well as power consumption and water consumption. These are kept together with the “record of build” which is completed and signed by each technician as stages in construction are completed. The result is a full record of the unit from when it was just a collection of parts and sub-assemblies to a fully operational system. Say what you do, do what you say!