Reports on analyses and experimental tests concerning fractionation effects with refrigerant blends. Refers to analytical models verified by laboratory data that predict the fractionation effects of hydrofluorocarbon (HFC) refrigerant blends 1) when exposed to selected POE lubricants, 2) during the system charging process from large liquid containers and 3) during system start-up, operation, and shutdown within various system components and during selected system and component leakage scenarios. Presents model predictions and experimental results for HFC refrigerant blends containing R32, R134a and R125. Generalises the data for various operating conditions and scenarios.

KEYWORDS: year 1997, Heat pumps, refrigerants, fluorocarbons, mixtures, housing, laboratory testing, calculating