Studies on the Condition of Vehicle Air Conditioning Systems - Two Years After Retrofitting HFC-134a

This paper is a continuation of a series of papers presented by ICI on the North American retrofit fleet with HFC-134a. Building on our last paper, which profiled this fleet, this paper describes the results of the studies in which a number of vehicles have been removed from test, and their air-conditioning systems examined. After an update on performance and service requirements, the paper provides results which include the conditions of the compressors and other components, the quality of the refrigerant and lubricant, and the amount of the refrigerant charge retained. This information will be correlated with previous information to determine the actual efficiency of previously employed clean-out methods. The data indicates existing OEM hoses and elastomers are likely to provide sufficient containment of HFC-134a in retrofit situations. Vehicles retrofit under a variety of procedures (flushed or not) have shown good A/C performance and compressor durability. The refrigerant and lubricant analyses, after the test period, suggest no degradation of the quality of either fluid.