hey guys and gals, I'm having trouble with my temp. I have an okie Joe longhorn and am using frontier brand lump and hickory chunks. I got it going today and was shooting for about 240*. it got there after about a half hour and I've been struggling to keep it at 225* or so. it even dipped down below 200* for a while. well actually right now they read about 160*. I have a lot of coal going, so much that to even stand three or four feet from the firebox you can feel the heat. I added two more thermometers to the door. one on either side of the handle and they read pretty close to the same on both sides. the chimney damper is wide open, and the firebox damper is too. I feel kind of ridiculous asking, but am I doing something wrong?