[Burlyman]

When we bought our coach the air compressor came on every 15 minutes, after watching a number of the videos on YouTube that Richard posted gave a very clear explanation of the systems and how to track down leaks but one tool that I bought has been a lifesaver in time and effort is a ultrasonic leak detector, my hearing isn't good but believe  me somebody with excellent hearing cannot hear in the ultrasonic range. I bought a used ultrasonic leak detector on eBay for a very small amount of money and it has been fantastic for finding more than just air leaks it also detects Freon leaks.

Finding Air AND freon leaks... Brilliant!  I'll look for this item, as my maintenance crew has somewhere around 100 AC units to maintain and service and they could certainly use one as well.

Thanks for mentioning this.  If I can get one shipped to me in time, it'll go with me on my trip next week.