I want to put a propane Hot Dawg (or similar) heater in my detached 24x32x9 garage, probably 45K. The walls and ceiling will be insulated/sheetrocked. My question is are there any issues if I only use the unit when I need it rather than maintaing a low temp? This is a vacation home that may not used for a month. I do want heat for projects, repairs and a place for the kids to play when the weather doesn't cooperate but can't justify the heating cost when no one is there. Thanks.