I cooked up slab of spares today and I put on some baked beans on the lower grate for the last 1.5 hours of the cook. For the first 4.5 hours of the cook the WSM held like a rock between 225 - 230 degrees. At the 4.5 hour mark I put on baked beans in a glass baking dish wrapped in foil on the bottom rack and added cool water to the water pan. After I put the beans on my temps immediatly went up to 255 degrees and held there for the rest of cook. I had all vents closed and still could not get the temp down. I think the foil may be conducting heat. I think I have the shiny side of the foil facing out. Any suggestions for next time?
