Brazed aluminum condensers for residential air conditioning

This paper provides an evaluation of the potential for use of brazed alumin um condensers in residential air-conditioning systems. Analysis was done to compare the performance of a brazed aluminum condenser with a presently us ed 2-row finned tube condenser having 7.0 mm diameter tubes. The comparison s were made for I-row brazed aluminum designs using 3 x 16 mm or 2 x 20 mm cross-section tubes, whose condensing performance has been measured. Used w ith a commercially available fin geometry at 26 fins/in, the 3 x 16 mm tube design will provide 35% material weight reduction and 15% lower pressure d rop, relative to the 7.0 mm round-tube heat exchanger. No cost reduction is predicted. The predicted air-side performance was verified in wind tunnel tests. An advanced fin design having a smaller louver pitch will use 22 fin s/in, and provide a 55% material cost reduction. The advanced fin geometry has 8.1 mm high fins, 12 louvers and 1.0 mm louver pitch. If a tube having 2.0 mm minor diameter is used, greater ail pressure drop reduction will be achieved, but at the expense of material savings.