Can you use a down draft as an updraft furnace?

yes u can if u are good with duct work put a down draft furnace in a basement and pipe it up one floor well not recommended it will work i did this to help a lady get threw winter who had low funds and it has worked quite well u need to build a custom box for the furnace to sit on to make this work and pipe directly from box and use smallest duct work u can i.e mobile home duct work or 4 to 6 inch

What you did is still a downdraft furnace