in this study, the possibility or introducing R1234ze(E) and Rl/34ze(Z) as a low-GWP refrigerant ror high temperature heat pumps is investigated. As the first trial, their cycle performances were thermodnamically analized. Next, the drop-in experiments of R1234ze(E) and R1234ze(Z), using a compressor developed for R410A were carried out. As a result, in the range of test conditions, volumetric capacity of R1234ze(E) is enough large for 2 kW class applications at the condensation temperature ranging 75℃. Volumetric capacity of R1234ze(Z) seems to be enough at codensation temperatures over 100℃. These results suggest that R1234ze(E) and R1234ze(Z) can be strong candidate as low-GWP refrigerant for nigh temperature applications.
