
Originally Posted by
Bill R.
don't cool as well as the original r12, I suspect that since our temps are a bit higher here even without the humidity that thats the reason so few work well here on r134a conversions. I'm speaking about all cars and primarily japanese since thats what i see the most of... It seems if the A/C system was oversize to begin with then r134 has the best chance of working well.. On some cars like the prelude and most japanese cars the compressor is just barely large enough to cool the car along with marginal sizing on the evaporator and condensor.. They work poorly here if you sit
at a stoplight too long even on the original r12 so on r134 the performance is pretty bad unless your on the highway for a long drive, then the car finally starts to cool down... Out of all the r134a conversions that I have done maybe 25% of the customers were happy with it... the other 75% weren't satisfied with the performance... Freeze 12 conversions i have done seem to work as good or even better than the original r12 setup
The epa stipulates that in order to use freeze12 you much evacuate the system of all r12, change the low and high pressure fittings so that no confusion exists over what refrigerant you now have in the system and label it clearly.. You can use the existing oil in the system with freeze 12, existing expansion valves work well as well as the stock condensor sizing.
I have talked to one of my parts suppliers out here who sells it and she told me that she sells a fair amount of freeze 12 now but very few commercial accounts buy the conversion kits with the fittings, which is what is causing a lot of the problems for A/C shops over freeze 12... Since it works fine in a
r12 system these shops (I don't know any names ) are just adding a can to a r12 system when its low on charge without evacuating the old r12 or changing the fittings and labeling it... So down the road when another ac shop works on the car, the first thing they do is check the system for contaminant gases before working on the car...and they find mixed gases in the system and won't work on the car since they don't want to contaminate their recycling equipment... Whereas if they had done a proper conversion which is easy with freeze 12 then any future shops that work on the car would know whats in the system and the fittings would theoretically prevent them from adding the wrong refrigerant to the system. So the only real problem here with freeze 12 is that it mixes just fine with r12 and cools as well making it easy to misuse in the eyes of the epa and repair shops who have to purchase recycling equipment for each form of refrigerant out there... But back to the beginning.... As far as perfomance and compatibility with the stock system, the cars i have converted to freeze 12 have cooled much better , there are a couple of things that they recomend to make it work better, one is if the system is old then a new accumulator/filter/drier is always a good idea and since a portion of the blend of freeze 12 is r134a they recomend 3 ounces of ester oil be added to the system... But all this is just speaking from my own experiences here in the hottest part of summer... If my own car was leaking too much r12 I would probably fix the leak and recharge with 12 since I have plenty of r12... but if i was out of r12 then I would convert to freeze 12, If my compressor had died and i had to replace a lot of components I might consider r134a since the compressor manufacturers are iffy about warrantying compressors if you have used any alternate refrigerants. But for me personally I would probably still use freeze 12...
This probably doesn't help you much , its one of those things where you actually have to be here and experience the performance of each for yourself....