Possible new working fluids in high-temperature heat pumps

Due to the CFC-problem a high R&D activity on new fluids isnow going on. This is also the case for high temperatureapplications, which here are defined as systems having condensing temperatures above approximately 70\ub7C. In the following various alternative fluids, both pure ones and mixtures now being investigated, are discussed. Although one of the important problems with new fluids is the lack of data, several data for interesting high-temperature working fluids have now been published. Examples of such publications are given in references 1-15. In the calculations done for the results presented in this paper, the data given in these and other references have been used. However, in several cases no data have been available except e.g. normal boiling point and molecular weight. In such cases data have been estimated with methods traditionally used in chemical engineering