kyporsche87

Ok I have my 87 944 going and in checking my a/c the compressor is not kicking in what is the list of things to start checking. Can I change it over to R134 and if so can it be done just like american cars ect.........?

jwade944

There is a pressure switch that prevents the compressor from running if the charge is low.

kyporsche87

thanks and I understand that. Is there any problem with changing it over to 134-a ?

jaje

I'm going through this issue right now. R134 is much cheaper to buy and more environmentally friendly but the a/c does not get anywhere near as cold as R12. Mine was switched over to R134 and works ok but I may swap it back to R12 so that my a/ works really good. You may also want to replace the drier as if there's moisture in there it will reduce the effectiveness.

We were diagnosing my a/c last night and found that first you want to check your system by a vacuum test (no not a hoover - just reverse it from pressure to vacuum!) and letting it sit for 5-7 minutes. If the vacuum is still at the same level then your system at least holds vacuum and should hold pressure. Then start adding in the freon and pressure to see if the system turns on. My compressor didn't switch on so we checked the switched and a couple of the wires were disconnected so we resoldered them and it worked on mine. Have some experienced do this and with the right equipment.

kyporsche87

Thanks alot. I have changed about 10 or so other cars (not porsches) over to the R134 with no major problems. So before I jumped in and started on my Porsche just wanted to make sure. Yes the R134 does not get as cold as th R12 unless it is driving down the road. The biggest problem I have had in the past with just a couple of my former change overs has been as in sitting at a red light or waiting in the parking lot for my wife. So when that did happen I would just ride around instead. Please keep the A/C tips coming !!!!

John_AZ

Have you seen these tech articles? Click on AC R134a. http://www.the944.com/

John_AZ