I just got an 80-110,000btu propane heater for my shop to get it warm enough for glassing the Arctic Tern I am building. I tested the heater last night as I was filling the hull seams, with the heater hooked to a 20lb bottle. It put out great heat for a little while, but the propane bottle began icing up on the outside and the heat output was greatly reduced. The manual for the heater recommends a 100lb bottle. Is that size to combat the icing? What sizes are you all using? Could I get away with a 40lb? The 100lbs are only $20 more than the 40lb bottles, but dont look to be very easy to handle when full.

Thanks!
Miklos