Terry:
I recently bought a propane heater that is specifically designed for
tent use, RV, boat, etc. It takes a 1 lb propane canister but can also
be hooked up to the large tanks. Easy to light, light weight.
Instructions are emphatic about having a minimum of 8 sq.in. of fresh
air available, i.e., a 8"window opened an inch wide would suffice, etc.
It cost $99 at a marine supply place but I've seen similar models in
Cabela's catalog. Haven't "lived with it" yet however so I can't give
you first-hand advice.
Jo Ann