I hope it is bad gas, unfortunately i have no time to exchange it this week now since this was my only day off and they are already closed. I tried it on some cold rolled steel in DC and it seemed to work fine? I didn't really get any pinholes or anything. I flipped it back to AC and can hear the frequency so i know AC is coming on, but there is absolutely no ac cleaning at all. every once in a while it will kind of start to come back then go away again. I got the bottle from Praxair, and I'm not going back to the place after i swap the bottle anyway. last three times I've gone in the fill rate went from $35 to $45 an today $56.....less then a month on all three, wtf.