It's a Gas

Today we have discovered that different size propane bottles can have fittings that are thread-compatible (that is, they have the reverse-thread fittings and can be physically connected) but are not actually compatible with each other. That means you can end up connecting a bottle to your system that appears to work (and does, to some extent), but is actually also slowly leaking propane from the fitting. Leaking propane is a Bad Thing. Tomorrow I need to contact a local propane service who claims to have the kind of adapter we need. I really hope it works, because otherwise we're out the investment in a new bottle (the store won't take it back as it has been used and has propane in it) and in 15 gallons of propane to boot.

Both Lisa (whose family had multiple RVs and travel trailers) and I think that it is amazingly stupid that you could design fittings that can appear to connect properly but that actually are explosions waiting to happen, and that all the vendor will tell you is, in effect, "Well, you just have to know about it." I wonder how many propane explosions have been caused by this.