Briefly discusses ozone-safe refrigerants that could potentially replace the fully halogenated CFCs now used in many centrifugal chillers. Based on comparisons of normal boiling points, concludes that R123, R123a and possibly R152 and R141b appear promising alternatives for CFC11. Five refrigerants (R134, R22, R134a, R143a and R152a) appear promising replacements for CFC12. Three refrigerants (R22, R134a and R32) appear to be promising replacements for R500. Four non-azeotropes appear as possible replacements 142b and R22/142b.

KEYWORDS: R141b, R12, non azeotropic, refrigerants, fluorocarbons, centrifugal compressors, chillers.