As others stated, run your furnace in the driveway to burn off oils, etc in the system (usually about 30min).
Have an electric space heater to keep temps cozy inside so you don't run furnace all day & night.
Electric blankets are awesome for night time so furnace can be set on lower setting to prevent using all your propane in 2-3 days.
Enjoy winter camping, one of the best times of the season...no bugs or sunburns