After many fine years, the over the road air system on our H3-40 decided to give up. According to Prevost, it is leaking in more than one location. This would not be a huge issue EXCEPT that our coach was one of the last made using R-12 refridgerant. The R-12 is very expensive with no guarantees it won't leak out somewhere else if we fix the leaks. The cost to convert the system to R-13/14a refridgerant is enormous as all the lines from end to end and most of the AC equipment needs to be replaced. If anyone else out there has had to face this issue, I would love to know what they decided to do.