Retrofitting an automotive air conditioner with HFC-134a, additive, and mineral oil. Final report, October 1992-May 1994

The paper gives results of an evaluation of a lubricant additive developed for use in retrofitting motor vehicle air conditioners. The additive was designed to enable HFC-134a to be used as a retrofit refrigerant with the existing mineral oil in CFC-12 systems. The goal of the project was to provide preliminary feasibility testing of the additive. The cooling effect of the test system retrofitted with HFC-134a and the oil additive was nearly the same as that of the original system with CFC 12 refrigerant. If lubricant additives prove to be successful, miscible lubricants may not be needed for retrofitting some automotive systems. The retrofitting procedure might be simplified and the cost to consumers might be reduced. It has not been determined if retrofitting systems with HFC-134a and oil additives is feasible for a wider range of operating conditions and types of equipment, including the applicability of orifice tube/suction accumulator systems.