Hey all, I just recently purchased an hs tarm 502 used. The people before me burned pine in it and after I got it I scrapped all of the dried on sap off in the fire box and in the box where the 12 flu pipes are. I had no problems just burning wood but, when it got colder and I switched to coal I started to have a real bad problem with soot. I now have to take every thing apart and shop vac it about ever 5-7 days(it clogs up those six pack of pipes completely). I am not sure if I am doing something wrong or if its my coal. If anybody could help me out here Id greatly appreciate it. Also where there are those two sets of six tubes for the fire box and the oil burner there is a metal plate in there and six heatsinks(not sure of what they are). I have the heatsinks on the oil side now and that plate resting over the six oil flu pipes. I am not sure exactly what to do with those either. I do not use the oil side at all at this time. It seems to be drafting good I can feel it pulling from the bottom flap.