0wantthis0havethis  Mr. Heater Portable Propane Heater is safe for indoor use in small recreational enclosures, having means for providing combustion air and ventilation, such as enclosed porches, cabins, fishing huts, trailers, tent trailers, tents, truck caps and vans. It may be used in commercial enclosures, having means for providing combustion air and ventilation, such as construction trailers or temporary work enclosures. When the heater is cold or at room temperature, it will take a few minutes for the burner(s) tile to turn bright orange. This is normal and...