Hydroflurocarbons (HFCs) include such refrigerants as R134a and R-23. They are different from chlorofluorocarbons they contain one or more hydrogen atoms and no chlorine atoms. HFCS are considered to have zero potential for ozone depletion. They have only a slight effect on global warming R-134a is typically used in new system that are specifically designed for its use. The concept that R-134a is easy replacement for R-12 is not correct however’ When using R-134a in retrofitting a system, numerous items must be considered. R-134a refrigerants will not readily mix with mineral oils or alkylbenzene lubricants. Synthetic oils must be used for
lubrication of hydroflurocarbons, existing oils must be replaced. ‘
The use of the Proper recovery unit is necessaries for the removal of R-12. There are also a number of other
factors to be considered. These include system Performance, hardware changes, and existing material and lubricant compatibility.