So im posting this in the hearth room because my furnace is basicly like a wood stove with a metal cabinet around it. Its a US Stove company wood/ coal furnace. My question is what should I be running for temp on the outside of the single wall pipe. The setup is 6 ft of 6 inch single wall with two 90s into a masonry chimney lined with 25 ft of 6 inch stainless insulated liner and 5 ft of class A out the roof (some jackwagon knocked the chimney down just below the roof line so that was interesting making that transition.) I get killer draft with this setup and dont want to over fire so I havnt been pushing it too hard but I can still get it to 80 in the house in about 3 hours. Here are some pics of the furnace.