as previously mentioned, i am heating with a harman sf160. i have 7" black smokepipe coming off the back of the unit, going up about 4-5ft. and turning into 7" all-fuel from there, 30' to the roof. i am picking up an infrared thermometer (cool, with the little laser pointer). what temps should i be getting on the smoke pipe to help prevent creosote buildup? should i be looking for a certain temp range on the firebox door/water tank?