New to the forum and would greatly appreciate any feedback i can get in my situation. Just took out a us stove hotblast 1500. I had the 2 8" heat supplies tied into my l.p. downdraft furnace plenum which made my runs go over and down a couple of feet instead of up. Worked ok for 20 years even though I'm sure it was not ideal. I am currently looking at a shelter sf3100 and the installation instructions say that the ducts must run horizontal or up. Do you think i could get by with the same configuration like before ? I don't really have any anywhere else to make the connection.