So, with both stoves cruising at 500F, running 2.5 full loads per day, we're still barely keeping temps up to 68-70F, and often running some oil. I've also noticed how hard it is to hold these stoves below 500F with some types of wood (particularly Walnut, believe it or not!), without getting into catalyst over-temp situations, and it's hard to get the cat to light off (even with my better dry wood) without getting the stovetop up to at least 650F. It's got me thinking... I may be measuring the wrong temperature, and thus running these stoves way too cool! Here's what I know: 1. The Firelight 12 specifies no location for any thermometer, or any range of safe or maximum operating temperature. 2. The Firelight 12 has a cast iron top load door (single layer, webbed, maybe 5/16" thick), upon which I've been measuring my temperatures. It's the hot spot, and very responsive. 3. Jotul does specify a thermometer location for the Firelight 600, which is the non-cat twin to my stove, this location being the rear corner of the stove top. These stoves share most of the same castings, but the F600 lacks the top-load door of the F12, thanks to the reburn system. 4. When I see 600F on the top load door, I see only 400F at the rear corner, where I'd be running the thermometer on the F600. So, am I running my stove at "400F", or "600F"? More importantly, when I'm cruising all day at 400F on the top-load door, am I really running the stove at "250F", the temperature I would see on the F600-specified thermometer location?