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sick kiln

updated wed 6 feb 08

 

Digital Studio on fri 1 feb 08


We have a kiln here on my college campus that insists on erroring when
it gets close to temperature. We're doing ^6 with a Easy-Load (Front
loading) L&L Kiln. I'm not sure how long we've had it here... maybe 5 or
6 years? Just a guess. My teacher put in a glaze fire on fast Wednesday
morning. When I came back the next morning, he said it errored out at
2007 degrees when the middle and bottom were too different in
temperature (around 50 degrees). He went ahead and started it up again.
I stayed there to watch it until midnight, when it errored again at 2000
degrees. I started it back up and after 45 minutes it errored at 2023
with a 60 degree difference from the middle and bottom sections, the top
hasn't been a problem, it's usually within 5. I know it could be any
number of things... but what do you all think this could be? And what
about the ware I had in the firing? Can anyone tell me a little bit
about what happens when you underfire and re-fire correctly and how that
can change your result?
(Also... more new tests on my Flickr:
http://www.flickr.com/photos/digitalstudio)
Thanks to Alisa Clausen and Jaimie Yocono for recipes.

--
Kendra Bogert
www.digital-studio.biz
641-208-6253

Michael Wendt on mon 4 feb 08


One quick diagnostic tool is to move the
thermocouple from the bottom to the middle
and the middle one to the bottom.
If your offset continues at the bottom, it
is the elements.
If it now occurs at the middle, it is the
thermocouple.
Regards,
Michael Wendt
Wendt Pottery
2729 Clearwater Ave.
Lewiston, Id 83501
U.S.A.
208-746-3724
wendtpot@lewiston.com
http://www.wendtpottery.com
http://UniquePorcelainDesigns.com

gayle bair on mon 4 feb 08


Kendra,
After all kinds of fixes including buying & changing all the
thermocouples
I removed the top and bottom thermocouples and just rely on the middle
one.
Since then, according to my test cones, I have had the most even fired
loads ever
and no more error codes due to teh bottom thermocouple reading
stalling temps.
Now you may get better fixes but this is the one that worked for me.
Gayle Bair
Tucson AZ
Bainbridge Island WA
gayle@claybair.com
www.claybair.com




On Feb 1, 2008, at 2:46 PM, Digital Studio wrote:

> We have a kiln here on my college campus that insists on erroring when
> it gets close to temperature. We're doing ^6 with a Easy-Load (Front
> loading) L&L Kiln. I'm not sure how long we've had it here... maybe
> 5 or
> 6 years? Just a guess. My teacher put in a glaze fire on fast
> Wednesday
> morning. When I came back the next morning, he said it errored out at
> 2007 degrees when the middle and bottom were too different in
> temperature (around 50 degrees). He went ahead and started it up
> again.
> I stayed there to watch it until midnight, when it errored again at
> 2000
> degrees. I started it back up and after 45 minutes it errored at 2023
> with a 60 degree difference from the middle and bottom sections, the
> top
> hasn't been a problem, it's usually within 5. I know it could be any
> number of things... but what do you all think this could be? And what
> about the ware I had in the firing? Can anyone tell me a little bit
> about what happens when you underfire and re-fire correctly and how
> that
> can change your result?
> (Also... more new tests on my Flickr:
> http://www.flickr.com/photos/digitalstudio)
> Thanks to Alisa Clausen and Jaimie Yocono for recipes.
>
> --
> Kendra Bogert
> www.digital-studio.biz
> 641-208-6253
>
> ______________________________________________________________________________
> Clayart members may send postings to: clayart@lsv.ceramics.org
>
> You may look at the archives for the list, post messages, change your
> subscription settings or unsubscribe/leave the list here: http://www.acers.org/cic/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at melpots2@visi.com

Patty Kaliher on mon 4 feb 08


Call L&L. Their support people are very helpful. An extreme difference
between thermal couples may mean ware is packed to close to one of them
(more likely in bisque). Or something needs to be replaced. The people at
L&L can tell you what buttons to push on the controller to diagnose the
problem.

-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of Digital Studio
Sent: Friday, February 01, 2008 4:47 PM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Sick Kiln

We have a kiln here on my college campus that insists on erroring when
it gets close to temperature. We're doing ^6 with a Easy-Load (Front
loading) L&L Kiln. I'm not sure how long we've had it here... maybe 5 or
6 years? Just a guess. My teacher put in a glaze fire on fast Wednesday
morning. When I came back the next morning, he said it errored out at
2007 degrees when the middle and bottom were too different in
temperature (around 50 degrees). He went ahead and started it up again.
I stayed there to watch it until midnight, when it errored again at 2000
degrees. I started it back up and after 45 minutes it errored at 2023
with a 60 degree difference from the middle and bottom sections, the top
hasn't been a problem, it's usually within 5. I know it could be any
number of things... but what do you all think this could be? And what
about the ware I had in the firing? Can anyone tell me a little bit
about what happens when you underfire and re-fire correctly and how that
can change your result?
(Also... more new tests on my Flickr:
http://www.flickr.com/photos/digitalstudio)
Thanks to Alisa Clausen and Jaimie Yocono for recipes.

--
Kendra Bogert
www.digital-studio.biz
641-208-6253

____________________________________________________________________________
__
Clayart members may send postings to: clayart@lsv.ceramics.org

You may look at the archives for the list, post messages, change your
subscription settings or unsubscribe/leave the list here:
http://www.acers.org/cic/clayart/

Moderator of the list is Mel Jacobson who may be reached at
melpots2@visi.com

Randy O'Brien on mon 4 feb 08


I had a similar problem last year, but with an external wall mount
controller.
It would make it up to around 1500 degrees and then I would get an error
message that it wasn't climbing fast enough and shut itself off. I
started it up
again and it worked fine at low temps. Sounded like the elements were
bad, right? Only this came on suddenly, not a gradual deterioration in
performance. What happened was occasionally the contactor
switched into the on position and no power came through. But when it
switched
off and then back on, it worked. At low temps this wasn't a problem. It
switched on and off, sometimes not working, but it was able to maintain
a decent climb. When it hit 1500 degrees or so, and it happened to be
one of the times that the power didn't go through, the temp would start
to fall, the controller thought it was giving power to the kiln and
continued
trying to give full power to the kiln without doing the normal click
on/click
off and then eventually shut itself off when the temp fell enough. Maybe
this is the problem with one of the lower contactor relays in your kiln.

Randy
http://www.dakotacom.net/~rdobrien



Digital Studio wrote:
> We have a kiln here on my college campus that insists on erroring when
> it gets close to temperature. We're doing ^6 with a Easy-Load (Front
> loading) L&L Kiln. I'm not sure how long we've had it here... maybe 5 or
> 6 years? Just a guess. My teacher put in a glaze fire on fast Wednesday
> morning. When I came back the next morning, he said it errored out at
> 2007 degrees when the middle and bottom were too different in
> temperature (around 50 degrees). He went ahead and started it up again.
> I stayed there to watch it until midnight, when it errored again at 2000
> degrees. I started it back up and after 45 minutes it errored at 2023
> with a 60 degree difference from the middle and bottom sections, the top
> hasn't been a problem, it's usually within 5. I know it could be any
> number of things... but what do you all think this could be? And what
> about the ware I had in the firing? Can anyone tell me a little bit
> about what happens when you underfire and re-fire correctly and how that
> can change your result?
>

William & Susan Schran User on tue 5 feb 08


On 2/1/08 4:46 PM, "Digital Studio" wrote:

> My teacher put in a glaze fire on fast Wednesday
> morning. When I came back the next morning, he said it errored out at
> 2007 degrees when the middle and bottom were too different in
> temperature (around 50 degrees). He went ahead and started it up again.
> I stayed there to watch it until midnight, when it errored again at 2000
> degrees. I started it back up and after 45 minutes it errored at 2023
> with a 60 degree difference from the middle and bottom sections, the top
> hasn't been a problem, it's usually within 5. I know it could be any
> number of things... but what do you all think this could be? And what
> about the ware I had in the firing? Can anyone tell me a little bit
> about what happens when you underfire and re-fire correctly and how that
> can change your result?

First thing - drag out the instruction manual and look up the error codes.
They're listed in there and tells you what to do about them.

Most likely the kiln is programmed in a heating ramp that the kiln can't
maintain, thus the error code. This may lead to the need to replace the
elements, but that's jumping ahead at this point.

Slowing down the heating ramp around 2000=B0F may solve the problem.

Bill

--=20
William "Bill" Schran
wschran@cox.net
wschran@nvcc.edu
http://www.creativecreekartisans.com

Ed Bull on tue 5 feb 08


Lots of good advice so far... I'd add a couple of things.

We have five L&Ls in our studio.
Some are fired over a hundred times a year.

Check that error code!

I've found a kiln log invaluable in monitoring the health of our kilns.
Slow increases in firing time reflect element wear.
A problem that comes on rapidly usually indicates a more serious problem.
I could be the solenoid switch, element failure, or bad connections.

If glaze gets on an element it will eat through it and cause a break.
Sounds like your kiln has been used for years, so I'd suspect an element
problem.

You can visually inspect the elements.
Since it might be the bottom, you can use a mirror and flashlight to look
at
the bottome elements. If you see any glaze on the holder above the
elements,
check that part carefully. It might be as simple as replacing elements.
We do that in-house here at our studio.

Sometimes I just turn an empty kiln on fast to see if all the elements are
glowing.

Also, you should look at the big plug.
Make sure you turn off the breaker in the breaker box first.
Often these plugs are heavy and want to hang down, causing a poor
connection
which may arc and damage the plug or receptacle. Be careful here.

Another problem we found is on the place just outside the kiln
where the elements are tied to the wires running to the solenoid.
Make sure you don't see anything glowing by looking down through
the vents on top of the controller. Loose connection usually.

Taking apart the controller, you might want to check all the connections
for any sign of problems. Discoloration or brittle wires.

These kilns are a lot simpler than you'd think, and you can figure out a
lot yourself.
Also, Rob Battey at L&L tech support is great.
His email is rob@hotkilns.com

Cheers and good hunting,
Ed Bull
www.CreativeClayStudios.com