I have aquired a free woodburner with 4 blowers, and some misc piping (stove pipe and 8" duct pipe). I have the thing in place, one blower (more than enough) attached and wired in, and the ducting is piped into my furnace ducting and to a room that is notably cold all winter long (french door, garage door, very little insulation on a concrete floor). All is well. I have it up on low bricks right now on a cement floor 30" away from the back wall and will be putting a cinderblock wall around it just to be safe. Next year I planned an addition to the garage that will put this thing in a full masonry chimney, but that is going to have to wait another year as I will be deployed then. So this has to last safely for two years. I was told by others I am being too safe as it is a "cased" burner (?) which I guess doesn't have the same exterior temps as my little fireplace insert. Better safe than sorry. The opening is 7" right off the back of the case. The previous owner put an elbow right there, but that can come off. I would run the pipe the same size, but getting a hold of 7" stuff is so hard and expensive. Not to mention they need 3-6 weeks to get it out. I am considering either going up to 8" or down to 6". I need some advice on this. It is a large piece compared to others I have seen and is rated for coal burning as well though I doubt I ever will. I was told it would heat the entire house (3000sqft), and was used to heatr a 1500sqft garage before with no ducting, just blowing out the two eight inch outlets. Any help would be apreciated. I am trying to do this both economically and safely. I can get pics once I figure out how the wife messed up the camera, but things are a mess right now out there as I take care of a few projects before bow season opens.