I live in Western NC and have a 1200 square foot, single story home. I currently heat with an oil furnace and have existing ductwork under the house. I have a crawl space, not a basement. I would like to add a hot air furnace to supplement what I have now and reduce my heating costs. I will be using wood heat about half the time with the oil furnace picking up the rest. Is there any way to install a supplemental hot air furnace outside (in an outbuilding of course)? Everyone I talk to says the hot air duct cannot go down, only up. I would have to send the air down a few feet to get it low enough to enter the crawl space and connect to my existing ductwork. Also, what's the maximum distance the furnace should be placed away from the house? Would it be beneficial to bury the duct going to the house? Any comments, opinions, or suggestions are welcome. Thanks.