I have a lab grade probe and a couple of Rutland thermometers. I have a small fire going to take the chill off. Probe is close to 500. Rutland below it is 200 and stove top Rutland is 450. It is a lazy little fire but hot enough to not make creosote, some well seasoned maple and birch rounds so nothing serious. I woke up a bit cold at 3:30 am so the reason to start a small one. It has to make you wonder how many millions of cords of wood that have been wasted trying to keep a cheap thermometer happy.