I've got the us stove 6220, anyway, it has the big 10" duct work coming out of the top of it. I put it in my basement, and really don't want to tie it into my existing duct work, but want to get the heat upstairs a little better....so my question is this, can I use that flex duct they make for furnaces and tie it into a register (to kind of work like the old gravity furnaces)? That way I can remove the flex duct in the summer..so it's not permanant