I suggest that you adjust the Kiln Sitter with a firing gauge and add witness cones to several shelves. I agree that the witness cones are more accurate than a pyrometer.
A quick diagnostics pointer for your SnF-24: The elements in the SnF kilns are wired in series. If the top three elements light up, you know that all the elements in the kiln are working. This is because each of the top three elements is wired in series with other elements.
Your kiln project was like attending an in-depth maintenance seminar. Congratulations on getting your kiln running.
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