Results from previous testing of the Lorenz-Meutzner refrigerator/freezer using R32/R124 (zeotropic mixture) were published in an ASHRAE paper (Sand et al 1993). These results showed performance gains of approximately 3% over R12. In the study presented in this paper the Lorenz_Meutzner refrigerator/freezer having two evaporators and two intercoolers was experimentally tested in an environmental chamber according to Association of Home Appliance Manufacturers/Department of Energy (AHAM/DOE) testing standards using several hydrofluopropane-based-zeotropic mixtures. The results are compared to baseline testing with R134a. The R245ca/R134a and R152a mixtures performed comparably to R134a. R245ca/R270 outperformed all zeotropic mixtures and R134a by at least 16%. A refrigerant sampling loop was also added to determine the running composition of the mixture and its effects on the performance of the refrigerator/freezer.

Keywords: year 1997, calculating, refrigerants, mixtures, comparing, experiment, testing, climate chambers, R134a, R245ca, R152a, R270, performance, lorenz cycle heat pumps, replacing, refrigerators, freezers, fluorocarbons

Units: Dual