How to convert to R134A?

[thirdstreettito]

Well, my trucks A/C needs charging, I have to convert it to charge it. How do I do this? Also, what is the commercial refrigerant that has the same compound as R134A but i colder?

[gchemist]

Try Freeze 12. You have to replace the accumulator, orfice tube, pressure switch and oil. A new pressure switch is required for R134. I'm not so sure on Freeze 12. Open up the system. Flush the system using a can of A/C flush through the lines and condensor. Or use isopropyl alcohol. Remove all the oil from the compressor. Refill using the correct oil. Replace all the o-rings on the lines. Put a vacuum pump on it. It should hold vacuum for 30-45 minutes. Refill using the proper guages.

Here is a nice write up for our trucks. http://www.chevytalk.org/fusionbb/sh...hp?tid/168431/

[thirdstreettito]

Thanks. I dont know what most of what you said is. The refrigerant I am talking about is something like 908 or 906 or 904, I cant remember which one, it is exactly like R134A but colder.

[AceX]

Just run 134. Its cheap, and available. I did the conversion in my truck (well, I had a shop that is very experienced with the conversion do it.) and I don't regret it one bit.

Besides that, I'll be doing a motor swap sometime this year or next year, and the compressor on that motor is set up for R134a. All I will have to do is make some new lines and off I go.

[Strodder]

R-134A works with higher pressures. Any weak points in your A/C system will leak. Especially your old hoses. I would stay with the R-134A because they it is inexpensive and easy to get. Most A/C recycling/Charge Stations have both. There is a lot of cross contamination out there with so many different kinds of Freons. And do take it to a professional. You'll get the best results, if they know what they are doing.