Kiln failure

artquestor · Post by **artquestor** » Sun Sep 28, 2003 1:46 am

I have searched the board and the archive and haven't found any post that fits my current problem. I have a Cress glass kiln, that runs on household current. Had it for about fifteen months, it's probably been fired about 75 times. I noticed recently that my kiln was taking longer to fire to full fuse temps although two days ago it worked fine. Today, after four hours it had only ramped up to 400. I cooled it down a bit and opened the kiln. There was an odd smell and some fumes when it opened and the Thinfire paper I used had turned a dark grey-brown. We have determined that power is coming into the elements. It may be an element failure but I'm curious about the fibre paper and the odor. Hope it wasn't toxic. Has anyone seen this before? Would appreciate any comments.

rosanna gusler · Post by **rosanna gusler** » Sun Sep 28, 2003 7:11 am

fiber paper always does that. it is the organic binder burning out. no big deal. as to the electrics, can not help much there. i would call the manufacturer. rosanna

artquestor · Post by **artquestor** » Mon Sep 29, 2003 12:22 am

Thanks Rosanna for your reply. However, in all the times I've used fibre paper, it's never burned out dark grey. I always end up with white remains! And, yes, I am looking at the manufacturer's web-site which is pretty good and has wiring diagrams etc.

rosanna gusler · Post by **rosanna gusler** » Mon Sep 29, 2003 1:29 am

this is probably the first time you stopped the firing at around 400f. after about 900f the carbon is all gone. rosanna

Tony Serviente · Post by **Tony Serviente** » Mon Sep 29, 2003 8:45 am

I agree with rosanna-Your kiln just couldn't get hot enough to burn off all the binder. If your kiln has multiple elements I would bet that you've lost one or more, leaving it limping along on impulse power. If you only have one element, it has to be a poor connection, which will not only get worse with time, as you've already seen, but also presents the risk of a fire hazard, as bad connections can really heat up. I think the fire risk is small, but don't fire up again until you check it out. Pull whatever covers you have and do a visual inspection. If it is a connection issue you will most likely see the problem. The junctions of two or more wires will look very blackened, and sometimes distorted. There are many electrical checks you could do, but without knowing your kiln and how it is wired I can't offer any advice. Any decent electrician should be able to help you diagnose the problem. There is one last, but not least, thing you should check. You mentioned that your kiln plugs into a standard outlet. Check out the outlet, meaning pull off the cover and look inside. The connection issue may reside inside the box, and if it does you jump to a high risk of fire hazard. Good luck, and remember, don't fire up again until this is straightened out.

artquestor · Post by **artquestor** » Mon Sep 29, 2003 9:20 pm

Thank you Rosanna again. Yes, you are absolutely right--I've never opened it up at 400 before! You know it's really reassuring to understand why something happened.
Thank you Tony for your sound reasoning and sensible warnings. I certainly won't be firing until this thing is fixed. Fortunately, I bought the kiln through a local kiln dealer and I believe they are quite experienced so it's probably on its way to visit the kiln shop.
Appreciate both of your time. Susanne