Expected duration: 3 - 4 weeks Hello, I'm seeking a practical design for a complete cooling system using a variable speed compressor for a small environmental chamber (1mx1mx2m). The cooling load is estimated to be 7000Whr/day (including transmission and internally generated heat). The chamber will be well insulated and the external temperature and thermal properties of the insulation have been taken into account in arriving at the total cooling load. The air temperature needs to be controlled in the range 12-25 C and to within +/-0.5C. The compressor unit should be able to receive an external voltage signal for controlling the compressor speed and the evaporator temperature. There is a need to be able to experiment with running the evaporator temperature both above and below the dew point (with relative humidity in the chamber in the range 35 and 70% with the lower level associated with the lower air temperature). The system should comprise commercially available components and the design should specify all parts including the condenser, evaporator, metering device, pipes, filter, fittings and mounting frames/brackets, connections, fans, recommended refrigerant, filling points, pressure measuring points with each listed component having a part number, supplier and estimated part price. General instructions for assembly and testing should be provided. The system is intended for use in the UK and should be compatible with 240V, 50Hz mains supply. Based on the initial proposal, there would be expected to be several iterations to the design. Kind regards, Griffiths
