Q – My 944 air conditioning worked fine last year but when I fired the car up this spring, there was no cool at all. I wonder if it is time to change the car over to the new Freon. Larry
A – If you are considering changing it over, and if it is empty, now would be the time; if the system is simply a little low on Freon, maybe not. First things first, find a shop that has some of the old R-12 Freon and get a diagnosis. In some cases, a simple pressure switch will cause the system to fail, or it might be a leaking valve, hose, or fitting. The fact that it ran last year is a good sign that it might not be too expensive.
As time passes, the R-12 Freon that your car came with new will get more and more expensive and recently I saw it for $75.00 per pound! By contrast, R-134 retails for only about $10.00 a pound. So if you have no major fault, keep it original, if you have lost all the Freon and you are facing a major repair to the system, change it over. The added advantage is that in years to come, as future AC work is needed, I expect R-134 to remain the most cost effective refriderant.