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electric kilns feeling the heat?

updated thu 4 jul 02

 

Cindi Anderson on tue 2 jul 02


This is very common. Every summer potters around the world start
complaining that their kilns aren't getting to temperature or are very slow.
Basically all the air conditioners are running, and it pulls the voltage on
the grid down. Some power companies purposely lower the voltage at peak
times so they don't have to produce as much power. So there's less power
available to the kiln.

Cindi

----- Original Message -----
From: "Judy Musicant"
> Twice in the past week I've experienced a problem firing each of my two
electric kilns. Important background - it's been up around 90 F. here in
New Jersey throughout this period, with the air conditioner going full
blast.

Earl Brunner on tue 2 jul 02


Hey, around here (in sunny Las Vegas) we run the AC and the kilns simultaneously
ALL the time! Otherwise we either wouldn't fire or wouldn't have AC. And of
course neither of those is acceptable.
Do you have any idea what the population of Las Vegas would be today if AC hadn't
been invented?

Tommy Humphries wrote:

> If the heat wave is causing everyone to run the AC then it could definitely
> have an impact on your firing times...you need to contact the power folks to
> find when the peak load is in your area, and try to fire around it...either
> that or get an accessory transformer for your kiln, but that is $$$
>
> Tommy
>
> ----- Original Message -----
> From: "Judy Musicant"
> To:
> Sent: Tuesday, July 02, 2002 6:37 PM
> Subject: Electric kilns feeling the heat?
>
> > Hey mudslingers,
> >
> > Twice in the past week I've experienced a problem firing each of my two
> electric kilns. Important background - it's been up around 90 F. here in
> New Jersey throughout this period, with the air conditioner going full
> blast.
> >
> > First, my small Skutt 818 took more than 4 hours after being turned to
> high to reach the point where the cones 5 and 6 were bent to my usual
> position. Usually it only takes one hour. Since this is an old kiln, and
> the elements haven't been changed for some time, I thought it's probably the
> elements, or some other mechanical problem with the kiln, although the last
> firing in this kiln went perfectly smoothly. This kiln has no controller,
> so I couldn't tell what temperaure it actually reached. The firing was
> okay, but not as good as usual after this long a soak.
> >
> > Then, a couple of days later, my 1 1/2 year old Cone Art had a similar
> problem. I've fired this kiln maybe 25-30 times since I've had it, so it's
> unlikely to be an element problem. Also, the previous firing was no problem
> at all. This kiln does have a controller, which I set to reach 2150 F. with
> a hold of 50 minutes. Usually, I need to turn off the kiln after a soak of
> between 10 and 25 minutes at 2150, based on how the cones look. This time,
> the kiln could only reach 2116 F., and this after 13 hours, whereas my
> normal firings take between 11 and 12 hours, depending on how densely I
> packed the kiln. This kiln was packed quite densely. Anyway, the kiln
> couldn't even hold 2116, but dropped back to 2113-2114. After a soak of 20
> minutes at this temperature, the cones looked right, and the firing was
> successful, as far as the pots go.
> >
> > Would this problem result from a strain on the power in this heat? We
> didn't experience any other electrical problems during this period. Anyone
> had this problem during a heat wave?
> >
> > Thanks.
> > Judy
> >
> >
> ____________________________________________________________________________
> __
> > Send postings to clayart@lsv.ceramics.org
> >
> > You may look at the archives for the list or change your subscription
> > settings from http://www.ceramics.org/clayart/
> >
> > Moderator of the list is Mel Jacobson who may be reached at
> melpots@pclink.com.
> >
>
> ______________________________________________________________________________
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.

--
Earl Brunner
http://coyote.accessnv.com/bruec
mailto:bruec@anv.net

Judy Musicant on tue 2 jul 02


Hey mudslingers,

Twice in the past week I've experienced a problem firing each of my two electric kilns. Important background - it's been up around 90 F. here in New Jersey throughout this period, with the air conditioner going full blast.

First, my small Skutt 818 took more than 4 hours after being turned to high to reach the point where the cones 5 and 6 were bent to my usual position. Usually it only takes one hour. Since this is an old kiln, and the elements haven't been changed for some time, I thought it's probably the elements, or some other mechanical problem with the kiln, although the last firing in this kiln went perfectly smoothly. This kiln has no controller, so I couldn't tell what temperaure it actually reached. The firing was okay, but not as good as usual after this long a soak.

Then, a couple of days later, my 1 1/2 year old Cone Art had a similar problem. I've fired this kiln maybe 25-30 times since I've had it, so it's unlikely to be an element problem. Also, the previous firing was no problem at all. This kiln does have a controller, which I set to reach 2150 F. with a hold of 50 minutes. Usually, I need to turn off the kiln after a soak of between 10 and 25 minutes at 2150, based on how the cones look. This time, the kiln could only reach 2116 F., and this after 13 hours, whereas my normal firings take between 11 and 12 hours, depending on how densely I packed the kiln. This kiln was packed quite densely. Anyway, the kiln couldn't even hold 2116, but dropped back to 2113-2114. After a soak of 20 minutes at this temperature, the cones looked right, and the firing was successful, as far as the pots go.

Would this problem result from a strain on the power in this heat? We didn't experience any other electrical problems during this period. Anyone had this problem during a heat wave?

Thanks.
Judy

Mercy Langford on tue 2 jul 02


Hi- If you had the ac on while the kiln was on that's probably it. I know it
happened to me. Chances are any that is high power likewasher,dryer,ac
should'nt be on when the kiln is on.. mercy

Tommy Humphries on tue 2 jul 02


If the heat wave is causing everyone to run the AC then it could definitely
have an impact on your firing times...you need to contact the power folks to
find when the peak load is in your area, and try to fire around it...either
that or get an accessory transformer for your kiln, but that is $$$

Tommy


----- Original Message -----
From: "Judy Musicant"
To:
Sent: Tuesday, July 02, 2002 6:37 PM
Subject: Electric kilns feeling the heat?


> Hey mudslingers,
>
> Twice in the past week I've experienced a problem firing each of my two
electric kilns. Important background - it's been up around 90 F. here in
New Jersey throughout this period, with the air conditioner going full
blast.
>
> First, my small Skutt 818 took more than 4 hours after being turned to
high to reach the point where the cones 5 and 6 were bent to my usual
position. Usually it only takes one hour. Since this is an old kiln, and
the elements haven't been changed for some time, I thought it's probably the
elements, or some other mechanical problem with the kiln, although the last
firing in this kiln went perfectly smoothly. This kiln has no controller,
so I couldn't tell what temperaure it actually reached. The firing was
okay, but not as good as usual after this long a soak.
>
> Then, a couple of days later, my 1 1/2 year old Cone Art had a similar
problem. I've fired this kiln maybe 25-30 times since I've had it, so it's
unlikely to be an element problem. Also, the previous firing was no problem
at all. This kiln does have a controller, which I set to reach 2150 F. with
a hold of 50 minutes. Usually, I need to turn off the kiln after a soak of
between 10 and 25 minutes at 2150, based on how the cones look. This time,
the kiln could only reach 2116 F., and this after 13 hours, whereas my
normal firings take between 11 and 12 hours, depending on how densely I
packed the kiln. This kiln was packed quite densely. Anyway, the kiln
couldn't even hold 2116, but dropped back to 2113-2114. After a soak of 20
minutes at this temperature, the cones looked right, and the firing was
successful, as far as the pots go.
>
> Would this problem result from a strain on the power in this heat? We
didn't experience any other electrical problems during this period. Anyone
had this problem during a heat wave?
>
> Thanks.
> Judy
>
>
____________________________________________________________________________
__
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
melpots@pclink.com.
>

Imzadi . on wed 3 jul 02


You probably experienced a "brown out" from your local power company. That
happens when there is many users draining power from the company all at once,
(ie. everyone turing on their air conditioners at the same time) and everyone
ends up with less electricity overall. Unless you live in a very old building
with old circuitry, (like my family's apt in NYC,) you would hardly notice
you were in the midst of a brown out. But being in an old building, we would
actually see the lights dim for several hours then after "peak usage" hours
suddenly the lights would flair up brighter, microwave would suddenly heat at
full power and time again, etc.

Imzadi

william schran on wed 3 jul 02


Judy - Could very well be the voltage you're receiving from electric
company. Hot day, late afternoon, voltage may well drop due to
increased demand at peak times - will surely slow down firing. Just
had it occur yesterday at school. Bisque firing that would usually be
done by 3/4pm went to 7 pm. I'm in Northern Virginia, temperature was
at mid 90's and of course we were out there doing the raku thing!
Bill

Cheryl Hoffman on wed 3 jul 02


Hey Judy,
I'm in Florida and I have to fire at night because of the same
problem. I thought the problem was with my kiln...even the repair guy said
it was the kiln and I needed a new mother board. My kiln would fail to
increase temp and actually start dropping, clicking on and off every second
or so, two degrees up then three degrees down. Before taking the bite and
buying a new mother board (like I know what that is) I decided to try a night
firing...no problem at all. I've since done all firings at night and have
not had a single failure. Try it at night & see if there's a difference.
Good Luck, Cher Hoffman

Cindi Anderson on wed 3 jul 02


Of course not everyone is going to have this problem of kilns underfiring.
It depends on many things. Las Vegas might not drop the line voltage during
high AC usage, because there is always high AC usage and they have sized the
system for it. You might have plenty of extra power in your kiln so you
don't notice a reduction. You might keep your elements replaced, so they
aren't old and marginal. You might be direct wired, as opposed to using a
cord and plug which results in some loss, especially if traveling a great
distance.

Some people are lucky to get their kilns up to temp during normal times, so
a voltage drop makes a big difference.

Cindi

----- Original Message -----
From: "Earl Brunner"


> Hey, around here (in sunny Las Vegas) we run the AC and the kilns
simultaneously
> ALL the time! Otherwise we either wouldn't fire or wouldn't have AC. And
of
> course neither of those is acceptable.