When I got my Monte, it blew hot air, I looked for R12, found it but they wanted too much $$ for an experiment. I put in a can of 134 and it worked for a week, I put in some "high millage/sealer and topped off with regular 134. I held up for about a month of blowing cold and leaked down, I topped it off 2 more times and it has been fine for over a year. However, once the outside temp go's over 85, you can't count on it being cold. When it's not blazing hot outside, I'm pretty sure I could keep icecream frozen infront of the vents. Still have to check the fan oil, that may help me...just don't have time to wrench.