Why does my kiln make a buzzing sound?

A gentle buzzing sound from a kiln is reassuring because it means the elements are firing normally. On a kiln that uses relays, such as digital kilns, a louder chattering, buzzing noise usually means a relay is about to fail. An infinite control switch that pops is also about to fail. It's important to observe the sounds of a kiln so that you can recognize when something is wrong. Machines tell us a lot by the noises they make. A good mechanic can tell what is wrong with an engine just by listening.