There is a safety feature in the propane system that will stop the flow in the event of a sudden fast flow, such as a propane line being suddenly severed in an accident or something.
It is possible to trigger this by opening the propane valve quickly. I know, because I did it once. Couldn't figure out why I had no gas to anything.
Try shutting the propane off, remove the hose from the bottle(s), then reinstall them in the usual fashion, then open the tank valve slowly.
It's worth a shot before you go replacing things.
2007 GMC 3500 dually ext. cab 4X4 LBZ Dmax/Allison - 2007 Pacific Coachworks Tango 306RLSS
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