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If an element burns out during a roast you will get a thermal dip warning shortly after the element stops working. Test for this with a subsequent empty roast test: see Roaster not heating. The roaster will show a ‘Heat too slow’ warning during the empty roast test and your element needs to be replaced.
If an element is malfunctioning (faulty thermal link, but element not burnt out) this can cause either thermal dip or thermal runaway warnings. This can be tested with a standard test roast:
recalibrate bean circulation,
use beans of average size and density such as most Colombian varieties,
roast a 120g batch, and
use the default profile (Kaffelogic Classic).
If thermal runaway or thermal dip errors occur during a standard test roast, the element is most likely faulty and needs to be replaced.
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