>>610357Propane's easier to deal with, and cheaper for heating applications. 3gal is really fucking tiny, but ... a westy won't need a 25k btu forced-air like mine either. Shit, a little catalytic will probably work fine in that small of a space, so 3gal is probably enough for a night or two depending on where you are and how cold it is.
Shouldn't be too hard to put a valve or two on the fitting and give yourself the option of an external 20lb'er.
Propane can freeze up... it's pretty rare though. One time a few years ago a buddy and I had planned on trailer-camping at the trailhead, got out there and it was about -40°F... regulator was frozen. Got a hotel for the night and the temp got down to -53°F.... none of the diesels in the lot started without a LOT of heat dumped into them (even the ones with block heaters installed and running, the fuel lines from the tank still gelled). Only a couple of the gas trucks started that morning. Glad we didn't camp out that night... at those temps it starts getting dangerous real quick.
Other than the exceptionally frigid nights, i've never had an issue. Designing the trailer/camper with that in mind helps too.
Buddy's furnace is mounted up front, his line makes a big "U" shape from the cylinder/reg mounted on the front of the trailer, loops underneath, then straight up to the furnace.
Mine, the hose/reg is on the front of the V in a box, hook it up when I get set up (cylinder's transported in the trailer, moved outside for use). Propane line comes straight into the wall, up between the rib of the trailer and the insulation, then along the inside top corner of the trailer to the furance mounted in the back. That's never frozen up on me.
Battery's kept in the heated area too, so it can't freeze. I may get a battery blanket for the truck's batt this winter.
Insulation's key though. 1" foil-backed iso board works great. Working on my 3rd sled trailer build, using 1" in the walls and 2" in the ceiling.
