Selecting the proper refrigerant will enhance safety and avoid downtime.
For both new equipment and retrofit situations, the hydrofluorocarbon-based refrigerant R-507 has been shown to have suitable properties and provide low temperature performance when compared to its chlorofluorocarbon-based predecessor R-502. Hydro-fluorocarbon-based R-507 is composed of HFC-125 and HFC-143a. Because these two compounds do not contain chlorine in their structure, they do not contribute to ozone depletion. General properties of R-507 and R-502 are listed in table 1.