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Tests have been carried out over a wide range of operating conditions on a single circuit plate-finned tube type of refrigerant evaporator, exchanging heat between ambient air and refrigerant R134a. Uniform and non-uniform air flow distributions were applied with the objective of studying the effects of non-uniformity on heat transfer. The experimental results revealed that, for a given total volume flow of air, heat transfer performances could be up to 15% better with a non-uniform flow where turbulence levels were also high. Extensive comparisons were also made between these measurements and predictions from a computer model. This was designed to simulate the thermal behavior of cross-flow heat exchangers on a tube segment-by-segment basis, allowing for flow non-uniformity. Predictions were found to match measurements satisfactorily for test cases involving uniform air flows and a relatively large temperature difference between fluids.