I have a 1996-ish T 36-SS-B that I'm living in while my home is being built. The furnace worked the first year but last winter it failed and the tech who came out said it was probably the control board (we'd already repaired the fan and checked the burner, etc) He said it might not be worth fixing because I expected my home to be finished before I needed the furnace again. I relied on a Heater Buddy for the rest of last winter. Now it looks like I'll be spending another winter in the camper after all, so I want to get the furnace working again. Besides the nice heat, the floor ducts will help keep the pipes from freezing. (I put on a skirt and insulate, etc.) According to my original documentation, the replacement part number for the DSI Board is 6215. I googled 'Hydroflame furnace, 8531-III, 6215" and several boards come up that don't look exactly like mine. I don't know how to tell which ones will work and which ones are too different. Can anyone recommend a replacement board? Thanks!