The Older Car
Up until 1993 cars with aircon used a very widely used refrigerant popularly called "Freon" but correctly known as Refrigerant12. By the late 1980's it was realised that this refrigerant was at least partially responsible for damaging the ozone layer. As a result most countries undertook to change using this refrigerant (a CFC) to an alternativerefrigerant with similar properties but which did not contain CFC's. After about 8 years a total ban on the use of R12 to maintain older vehicles was mandated. This was possibly not a decision based upon much thought but seems to be just hastily thrown together, a bit like the Dangerous Dogs Act in the UK. As a result the problem which was going to virtually disappear within a few years anyway has created more problems for those few cars with AC but which have a considerable economic life such as Ferrari, Aston Martin and Rolls Royce and also Agricultural tractors and Combines which also frequently have a long life. Almost all pre-1993 vehicles can be converted to the later refrigerant R134a and mostly not anything like so expensively as was forecast back in the 90's. If just one component can be renewed then most vehicles can be successfully altered to run with the later refrigerant without high cost. The alternative is to run the AC with a "drop-in" refrigerant. Although technically still feasible it is rarely the best solution by 2014.
Along with the lovely old classic cars which were originally fitted with an R12 system are the smallish number of very well preserved luxury models of more common makes - there are some beautiful BMW 7 series cars around complete with virtually all the modern goodies of a very expensive luxury saloon but at a fraction of the cost. This is just one example of very many makes - the Mitsubishi Pajero is another very different model which has many desirable modern qualities but still has an AC system designed to run with R12. As an example the pre-1993 Pajero can be successfully converted and charged with R134a for £105 + vat.
It has now been decided mainly by the EU but also followed by the rest of the world that R134a will gradually be phased out to be replaced by a refrigerant with a lower Global Warming Potential. There are no plans to forbid the use of R134a to recharge the AC of cars that need a recharge as was done with R12. There is currently a large argument on safety issues with this new refrigerant (HFO1234yf) mostly between Mercedes-Benz and the EU authorities which we AC professionals are following with much interest and some amusement. Daimler-Benz have now decided reluctantly to use R1234yf but intend to use another suitable refrigerant in the future with fewer disadvantages.