Experiences with next generation low GWP refrigerants in centrifugal chillers.

This paper provides experimental design experiences with new olefin based refrigerants R1233zd(E) and R514A in centrifugal compressor based chillers. Also included are some experimental experiences with R1224yd(Z). All these refrigerants provide specific environmental features of interest including very short atmospheric life, no impact to stratospheric ozone, ultra-low global warming potential, and good thermodynamic efficiency and all also offer preferred safety benefits since they are nonflammable. The paper will provide a review of thermodynamic cycle performance and heat transfer characteristics as well as chiller testing results. Reliability indicators such as material compatibility and chemical stability have been demonstrated to be favorable and results are presented comparing them to current refrigerants.