I would recomend that you not use this or any other alternative refrigerant in your A/C system for several reasons, 1) it costs more that 134a from your local parts house, 2) you are contaminating the system and if you take it into a repair shop at a later date to have them fix it correctly they will more than likely refuse to service it for you because it will contaminate there A/C recycling machine and charging station, ( and yes we do have test equipment to verify the proper refrigerant) 3) if you are not sure of how to service the system safely you can cause serious injury to yourself or others.

There is nothing wrong with doing repairs yourself and saving money, but do yourself a favor and find a friend who knows what they are doing to help walk you through the process, or find a good repair shop. Lots of shops won't mind telling you if you need major parts changed like compressor, hoses ect. and you can do that yourself if you are on a tight budget and take it back to them for final service. It never hearts to make friends with a mechanic, they come in handy once in a while.