Have you tried the gauges that mount between the tanks and the flex line? Some have a "fail safe" mode. I guess the idea is that if too much propane flows at too fast a rate, it shuts off in the gauge. Beats me, but sounds like a good idea, for Class A situation where LP is needed for fridge while traveling. Good luck with shoulder surgery, been there done that on one. delaying the other because that crap HURT.