I found out that there is an environment friendly replacement for R-22. It is HF-22A. A side benefit is that it compresses and expands easier and less is needed by weight and still be effective. Since it is easier on the compressor, the electric demands are lower and gets colder faster. My old AC unit is now cooling better and my utility went down by 50% from July (pre changeover) in August (the hottest month). It use to run all day to keep the temp at 80, now it cycles on/off every 20-30 minutes.