I think you have a problem. Something is wearing out but it could be expensive to have it fixed.

My suggestion is to start searching for a couple of people that fix kilns and ask how much they charge just to look at it. Last year a friend took an old kiln into a place we know and the husband fixed it for $150. which I thought was cheap. He charged $50. to look at it but applied that amount to the repairs. Good luck.

The elements in your kiln will age with time but it could be something else.Does your kiln have the 3-heat switches?I am not familiar with the Duncan kilns but we use Skutt, and most of the time all the kiln manufactures use the same kiln sitter, the same switches,etc.Sometimes the elements will make you think they are working but really they are not, sometimes they will burn in two but will still show connectivity until they get hot, this is when the coil will break apart.Just get a flashlight and start at the top and go down, there will be a darkened or black area where the coil burned apart.If its not the coil it may be one of the (3) three heat switches.Open the boxes and look at where the coils hook into the switch, wiggle the by hand, if there is any play then you have a bad three heat switch.Make sure to unplug the kiln before doing this.If this doesn't help email me directly and we will figure it out, theres not many things that can cause this.
Kenneth (kwgeorge1@alltel.net)