All Skutt kilns with KilnMaster Controllers are programmed to generate Error Codes when something goes wrong during a firing. These not only give you an indication of what the problem may be, they also often will shutdown the firing to protect your ware or the kiln itself. When an Error Code is generated it will appear in the display and, depending on your controllers age and the code, trigger the alarm. On older units it is important to make note of the code before you press any key to stop the alarm and clear the code. On newer boards you can go to the Diagnostic Menu and access the ERTF feature to see the last Error Code to occur along with the temperature it occurred at, the amount of time into the firing at which it occurred, and in addition it will run a full Diagnostic test.