When your elements are bunched in the corners and gray, and look like this, and the buzz-click of the kiln is sounding very sad and tired, it is time to change them:
Don’t be afraid of the electricity, just unplug the kiln, open everything up, and proceed to follow the video instructions so kindly provided by the kiln’s manufacturer. Just carefully remove the elements and feel free to change the relays and thermocouples while you’re there, as well, like such:
Also, if you find some nuts have fused to their bolts, don’t worry, just use a hack saw to remove them completely and replace.
And then you have a beautiful working system again, possibly even better than before.