Firing up kiln after 15 years

[sherbetfirings]

HI I have a top loading Cromartie kiln which I bought in 1996/97....she's not been fired up for the last 15 years. I've had her in the garage all that time, moving house once and until last week she had remained untouched.She's now in a new workspace and I want to fire her up but wondered if there was anything I should do or check before doing so after such a long time.
Elements have been hoovered, bricks/ wall are all in tact and thermocouple looks ok. Any ideas would be appreciated...many Thanks Sal

[Pat from Canvey]

I would just fire up a small test piece and see what happens. Have you fired the kiln previously? If that result was OK then I can't see that anything could have gone wrong in the interval.

[Lee - Kilncare]

Firstly, check all the connections are still tight and free from corrosion most importantly the earth.

If you have an R.C.D. (trip switch) on your house be prepared for this to blow as soon as the elements turn on. 15 years in a garage, even a dry garage will mean the kiln may have sucked in a fair bit of moisture from the atmosphere.
If this is the case you will have to dry the kiln and you can only do that by firing the kiln up to say 800c and leave it there for an hour or two and the only way you can do that is by taking the R.C.D. out of circuit or firing the kiln with the earth disconnected. The later is mega dangerous, especially if the R.C.D. is blowing because of a fault and you presume it is just moisture.
We have a caged area here that we use for this.

If the kiln fires without blowing the trip, listen to it. If there is the traditional quiet hum then all should be well. However, a screechy buzz will indicate that the contactor has not fared too well.

A good way to find out if all the elements are still working is to tear up small bits of newspaper, say 25mm square or so and place one piece in between the coils on each element.
Turn the kiln on for a minute or two then check the bits of paper, if the element is working it will leave a brown burn mark where the paper has been in contact with it. If the paper is fine, then the element is not working.

Hope that helps a bit.

My personal advice would be to get an electrician to give it the once over, at least to check that the earth is still sound if nothing else.

[sherbetfirings]

Thank you
I've taken her up to 70 degrees
sounded fine and seemed ok....
no tripping out...
I'll try out the element and paper check now and then run her on a cycle...
fingers tightly crossed.

[flame n fuse]

good advice from Lee. 15 years in a garage is quite a long time for electrical wiring, and you don't want something horrible to happen. I think it would be a good move to get an electrician to check it.

[sherbetfirings]

OK.....all elements worked fine.....
However lid isn't sitting tightly it seems as a minute glow last night emittind around the lid and she only reached 1152, rather than 1200 I'd put her on....so sat at 1152 for over and hour....before I went out to check she was cooling off!!
Turned it off at that point....Piece I'd put in has run off the firing paper and shelf and onto the bottom of the kiln and created a nice 1cm deep crevice...pot hole...

[flame n fuse]

Hmm, assuming that you're talking in fahrenheit, the glass shouldn't have run at that temp.

[sherbetfirings]

Ha ha not only has the kiln not fired up for 15 years but neither have I .....put my on farenheit cycle temps rather than C's....doh...

Will the new pot hole affect the kiln?

[sherbetfirings]

stupid, stupid, stupid, woman!

[Lee - Kilncare]

LOL if you are gonna mix up F and C it is much better the other way round :O)

I wouldn't worry about your pot hole. Chip out the glass and fill the hole with some fibre or something. Or the glass may continue to eat downwards eventually.

[sherbetfirings]

Thanks Lee..
I've set her off the right way round this time....
When you say fill the pothole with fibre...what fibre do you mean?
crushed up useless shelf?

[Lee - Kilncare]

nope, i mean some form of insulation, like a piece of brick of ceramic fibre or the likes if you use it, failing that the crushed up shelf idea will work fine....

[Pat from Canvey]

1152F if I'm correct, is about 622 C and at that temperature, the glass shouldn't run. Did you put it in for 1152 C? Did you put dams around the piece to stop the glass from flowing? If you don't have any dams, any old kiln shelf can be cut up with a tile saw to make dams. Fire cement will fill the hole in the bottom of the kiln. It's stocked by Wickes and can be used to glue fire bricks together.

[Moira HFG]

Are you sure you didn't set it for 1200ºC?

That would explain the glow, the struggle to reach temperature, and the glass running......

[sherbetfirings]

Moira and Pat, I had run my centigrade unit on farenheit figures....hence the catastrophe! 1100 C is a little too high!
I'm just a little rusty! Great result from the subsequent firing so everything is fine! Thanks for the pot hole filling tips.