200xth The problem I have had with this method is it is not always 5º. If the room is warm it might be 2ºF but when the room cools the walls of the enclosure drop and the deviation changes. I see a variable of 5ºF up or down. At times I see only 1ºF at other times I see 6ºF. My hot spot if the probe is on the UTH the temps may range between 90-85ºF this can change in as short a space as 24 hours. I don't like having that little control. I am an odd case my room temp is unstable and changes all the time.