Resulting design and construction criteria

Suitable compressors are required for R134a with a special oil charge and adapted system components. The normal metallic materials used in CFC plants have also been proven with ester oils; elastomers must sometimes be matched to the changing situation. This is especially valid for flexible hoses where the requirements call for a minimum residual moisture content and low permeability.

The plants must be dehydrated with particular care and the charging or changing of lubricant must also be done carefully. In addition relatively large driers should be provided, which have also to be matched to the smaller molecule size of R134a.