search  current discussion  categories  kilns & firing - flues & venting 

when to turn kiln vent off

updated wed 26 feb 03

 

Chuck Wagoner on mon 24 feb 03


I plug the lid (drilled) intake holes once my kilns reach temperature.
The fan is still pulling plenty of air at the base while limiting the
cold air going into the kiln. It slows the cooling time some.

Chuck Wagoner
Rockville, IN.

John Anthony on mon 24 feb 03


Hi all- I'm firing several lots of cone 6 electric tests, which is a
totally new
environment for me. I have never done anything with an electric kiln
except bisque.
I have just got a nice new L&L kiln with a computer controller and a
vent that pulls air out through the bottom of the kiln. I am firing to
cone 6 (2185ish) and holding for 20 minutes then cooling fast to 1900F
then at 125/hr to 1500. This schedule is from the J&R masteringglazes
website. My question is when should I turn the vent off- is it bad to
have it sucking a lot of cold air in the top of the kiln when the "crash
cool" segment is going on? Or when the slow cooling segment is
happening? Seems as long as the kiln is firing it will compensate, but
it can't compensate if it's off, so the top would cool way fast and then
it would take a long time to even out.
I'm testing some stuff of current interest- Mike Bailey orange, falls
Creek Shino, the CN Numeg/White Satin combination, etc. as well as some
Val C and J&R variations.
If I get anything nice I'll post some photos.

thanks
John Anthony

Arnold Howard on mon 24 feb 03


According to Orton, you can leave the KilnVent on throughout the entire
firing: from pre-heat through firing and cooling and down to room
temperature.

You probably will not have a problem in leaving the vent on during
cooling. If you are concerned about cooling too rapidly, you can shut
off the vent at firing maturity. (You should be near the kiln at that
point anyway to make sure the kiln shuts off.)

Sincerely,

Arnold Howard
Paragon Industries, L.P.
www.paragonweb.com




----- Original Message -----
From: John Anthony
> I have just got a nice new L&L kiln with a computer controller and a
> vent that pulls air out through the bottom of the kiln. I am firing
to
> cone 6 (2185ish) and holding for 20 minutes then cooling fast to 1900F
> then at 125/hr to 1500. This schedule is from the J&R masteringglazes
> website. My question is when should I turn the vent off- is it bad to
> have it sucking a lot of cold air in the top of the kiln when the
"crash
> cool" segment is going on? Or when the slow cooling segment is
> happening? Seems as long as the kiln is firing it will compensate, but
> it can't compensate if it's off, so the top would cool way fast and
then
> it would take a long time to even out.

Jonathan Kirkendall on mon 24 feb 03


John,

I leave my vent running the entire time the kiln is on. Depending on how
the kiln is stacked, sometimes the top shelf is a little cool (by a half or
quarter cone only), but I compensate by putting cooler glazes up there, and
it's never been significant enough to turn the vent off then back on when it
starts up again.

Jonathan in DC
snow and floods and wind, oh my!

-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG]On Behalf Of John Anthony
Sent: Monday, February 24, 2003 9:29 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: when to turn kiln vent off


Hi all- I'm firing several lots of cone 6 electric tests, which is a
totally new
environment for me. I have never done anything with an electric kiln
except bisque.
I have just got a nice new L&L kiln with a computer controller and a
vent that pulls air out through the bottom of the kiln. I am firing to
cone 6 (2185ish) and holding for 20 minutes then cooling fast to 1900F
then at 125/hr to 1500. This schedule is from the J&R masteringglazes
website. My question is when should I turn the vent off- is it bad to
have it sucking a lot of cold air in the top of the kiln when the "crash
cool" segment is going on? Or when the slow cooling segment is
happening? Seems as long as the kiln is firing it will compensate, but
it can't compensate if it's off, so the top would cool way fast and then
it would take a long time to even out.
I'm testing some stuff of current interest- Mike Bailey orange, falls
Creek Shino, the CN Numeg/White Satin combination, etc. as well as some
Val C and J&R variations.
If I get anything nice I'll post some photos.

thanks
John Anthony

____________________________________________________________________________
__
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.

John Hesselberth on mon 24 feb 03


Hi John

I also have an L&L with the vent fan that is wall mounted (the best
design, but that is a subject for another thread). I usually turn off
the vent when the kiln is down to about 1900F. No sense in having it on
below that, especially when you are firing down. Any nasties are out of
there shortly after peak temperature.

If you have the kind of vent fan that is mounted underneath the kiln you
might want to let it get a little cooler before turning it off just
because the fan is helping to cool itself. I suppose you could shorten
your fan life by turning it off too soon, though I don't have any
evidence of that.

Regards,

John
On Monday, February 24, 2003, at 09:28 AM, John Anthony wrote:

> Hi all- I'm firing several lots of cone 6 electric tests, which is a
> totally new
> environment for me. I have never done anything with an electric kiln
> except bisque.
> I have just got a nice new L&L kiln with a computer controller and a
> vent that pulls air out through the bottom of the kiln. I am firing to
> cone 6 (2185ish) and holding for 20 minutes then cooling fast to 1900F
> then at 125/hr to 1500. This schedule is from the J&R masteringglazes
> website. My question is when should I turn the vent off- is it bad to
> have it sucking a lot of cold air in the top of the kiln when the "crash
> cool" segment is going on? Or when the slow cooling segment is
> happening? Seems as long as the kiln is firing it will compensate, but
> it can't compensate if it's off, so the top would cool way fast and then
> it would take a long time to even out.
> I'm testing some stuff of current interest- Mike Bailey orange, falls
> Creek Shino, the CN Numeg/White Satin combination, etc. as well as some
> Val C and J&R variations.
> If I get anything nice I'll post some photos.
>
> thanks
> John Anthony
>
> ______________________________________________________________________________
> 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.
>
>
http://www.frogpondpottery.com
http://www.masteringglazes.com