Tried a burn with small ironwood rounds today...47 pounds of Ironwood, 5 of apple, 9 rounds total. Pretty cold out...around 0*F - with the air completely closed flue temps were 600 - 700*F for over 5 hours. About 6 1/2 hrs into the burn flue was down to 500F. Had a really active fire for the five hours. Stovetop temps, as read on cast iron next to flue discharge, never went over 450*F. 9 1/2 hours and down to large coal bed, stove 260, flue 350F. Could not close the air more, and so lost a lot of heat up the chimney. Spoke with Woodstock and they said to get a damper...which I expected but didn't really want to hear. Am not looking forward to the way it will look. One more thing when cleaning the pipe too. Oh, well. Should be my biggest problem. Woodstock would like to see the flue temp at 350 to 400 degrees. I'm a long way from that when I burn smaller wood. Large splits I can burn with an internal flue temp about 450 (if it isn't too cold or windy out), and I get a much longer burn time. So, I'll give ICC some business, get a damper, and have a new toy to play with. Wouldn't be surprised to find I can actually get a good deal more heat out of this stove than I have been, which would be pretty remarkable considering the heating job it is already doing. Anyone else having trouble keeping internal flue temps down? I have an internal chimney, and a long straight run of ICC chimney...a good 30 feet.