"EPA/600-SR-92-053." "April 1992." Caption title. At head of title: Project Summary.

The performance of an innovative heat pump, equipped with a distillation column to shift the composition of a zeotropic refrigerant mixture, was evaluated. The results of U.S. Department of Energy (DOE) rating tests and seasonal energy calcuations are reported with the main cycle refrigerant compositions. No composition shifting of the circulating refrigerant mixture was observed. To demonstrate the potential value of composition shifting, and ideal vapor compression cycle computer program was used to predict what the system performance would have been had the composition shifted. Seasonal energy usage calculations based on the computer predictions demonstrated that the effect of composition shifting on the heating seasonal performance factor (HSPF) was very small, increasing slightly with climate zone. However, the savings in auxiliary heat were found to be substantial. In the cooling mode, computer predictions showed pure Refrigerant-22 (R-22) to have a seasonal energy efficiency ratio (SEER) approximately 2% higher than a mixture of 20% R-13B1 and 80% R-22 by weight.