A new model and a novel approach are presented for correlation/prediction of refrigerant mixture phase equilibria. The excess Gibbs free energy in binary halogenated alkane mixtures is described by a recently proposed two-liquid theory with a regular solution reference for mixtures of nonpolar species. The single g(E) model parameter, obtained by correlating near-ambient binary vapor-liquid equilibria(VLE), is used in Wong-Sandler mixing rules in the Peng-Robinson-Stryjek-Vera equation of state to predict binary VLE at elevated temperatures. This model is applied to the tetrafluoromethane-chlorotrifluoromethane (R14-R13), tetrafluoromethane-trifluoromethane (R14-R23), and the trifluoromethane-chlorotrifluoromethane (R23-R13) binary systems. The one-parameter quasi-regular g(E) model provides good correlation of VLE for the binary systems at near ambient conditions. However, successful prediction of high temperature VLE depends on the accuracy of the g(E) model, the consistency of the EOS mixing rule model, and the method used to solve the model equations and associated material balances.