I installed 4 thermometers. The large unit is a gas actuated with a probe located inside of the firebox 1" from the top of the row of firebrick. It range is 400-1200F. The temperature is usually around 700F however I do have 1/3 of the firebox reduced due to the warmer than usual winter of '06. The smaller thermomter below the large unit reads the ambient basement temperture. I also have a 50-550F thermometer showing the temperature in the heat collector and a third unit reading the flue pipe temperature. Typically I see 200F in the heat collector and 180F on the flue pipe.
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