i recently came into possession of an older model earth stove and it has the large round pipe coming from the bottom that i see is a floor duct. I understand you have to use this in a mobile home, i built my own home and plan on installing it . Do I have to use the floor duct if I install it ?or is there anyway i block it off or just leave it? Im very new to wood stoves they are a bit different from fireplaces....