Ozone depletion and global warming phenomenon necessitates the replacement of chlorofluro Carbon (CFCs) from Refrigeration and Air-conditioning systems. Many of the alternative refrigerants being evaluated require synthetic lubricants, are less efficient, and have toxicity problems. One option to develop new alternative refrigerants is to combine existing non-CFC refrigerants to form a nonazeotropic/zoetrope mixture, with the concentration optimized for the given application so that the COP can be (maintained or) improved. This paper first discusses about the nonazeotropic mixtures and the characteristics and COP benefits of nonazeotropic mixtures will be discussed. Second, identifies a new dimensionless group to correlate performance impacts attributable to liquid-suction heat exchanger with R-12, R-134a, HC blend (91% R134a, 4.5% R-290, 4.5% R-600a)