The manual for my Osburn 1800i states that the max temp should be 840 at the cook top. Cook top as defined by the manual is the set of louvers that direct the blower air flow just above the door. That cook top is a removable peice of very heavy stamped steel. NO WAY that thing will ever get to 850. So I asked Osburn, and they stated in words clearly translated from French to English... Temp should be typically 500 on the surface under the cook top, with a 650 max.