The green gunk coating the now potato-chip shaped shelves and the bottom of the kiln is what's left of the pots that were in the kiln. That's right, the pots melted. I'm not exactly sure what caused this to happen on this kiln. It's typically caused by the cone sticking to the sitter rod, and we find a melted cone running down from the sitter tube, but there wasn't one in this kiln. There was no evidence of cone being in the sitter at all. Plus the shelves were laying in a pile at the bottom of the kiln, which is odd. Usually the shelves are still stacked. My best guess is that for some unknown reason the shelves shifted and bumped into the sitter tube, knocking out the cone but lodging against the sitter rod, thus preventing the sitter from shutting off the kiln. Once the kiln got hot enough to warp the shelves, the shelf blocking the sitter rod fell to the bottom of the kiln and the sitter shut off the power to the kiln. The big question is why the timer didn't shut it down. It could be that it was set too high, or it malfunctioned. It seemed to be working fine when I checked it, but it is a very old timer and could be sticking. The only way to know is to let it run a few times and see if it's working properly.
So the owner of the kiln has a decision to make: fix it or replace it. Due to the age of the kiln, I'm going to recommend replacing it. Fixing it will require a new floor slab, 4 new elements, 17 wall bricks, and 3-5 hours of labor. Ideally, we should also replace the timer. It's time for a new kiln!
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