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gas kiln firing instructions - found 'em!

updated thu 23 sep 04

 

Gail Phillips on fri 17 sep 04


Here it is, after poking around on the net -
http://www.users.bigpond.com/dcoggins/gasfiring.html

Hopefully, it will be what the gas company wants.

Wish me luck!

- Gail Phillips, Praying Mantis Pottery

"Sanity calms, but madness is more interesting." - John Russell=A0

wayne on fri 17 sep 04


Screw Luck! Skill! I wish you skill!...and the gas company
intelligence! (Because they need it!)
Kisses!
Wayne Seidl
Key West, Florida, USA
North America, Terra
Latitude 81.45W, Longitude 24.33N
Elevation 3.1 feet (1m)
----- Original Message -----
From: "Gail Phillips"
To:
Sent: Friday, September 17, 2004 10:23 AM
Subject: Gas kiln firing instructions - found 'em!


Here it is, after poking around on the net -
http://www.users.bigpond.com/dcoggins/gasfiring.html

Hopefully, it will be what the gas company wants.

Wish me luck!

- Gail Phillips, Praying Mantis Pottery

"Sanity calms, but madness is more interesting." - John Russell

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John Baymore on tue 21 sep 04


John,

Thanks. Unfortunately, dealing with a lot of this kind of stuff is very
common for me. This whole "political" side of things is a major topic in
my kiln design course I've been teaching since the 70's.


In my own experience with industrial applications, though fairly light
(90-100 cubic foot car kilns), there were no certifications other than
that by the local electrical inspector and the local plumbing inspector
in combination with the gas company engineer.


Real industrial units typically are a bit of a different breed. I
actively study what they do because they have some really great technology
and they REALLY know how to make them work well... but I don't build that
kind of stuff. I "steal" good ideas,.......and apply it to less
sophisticated units. Hank Murrow kinda' does the same kind of stuff.....
his kilns are great and he really knows what he is doing.

First of all... those industrial units typically are put in in "Industrial
Zones" or at the least commercially zoned locations. An awful lot of
potters kilns are put in in areas zoned residential or agricultural.
Often as business operations that are not in areas where business are even
allowed. So we often start out bucking city hall.

This is not to mention that over the years too many potters have put in
kilns illegally,....... and when that becomes an issue... it makes it
harder for others to put kilns in later. And I have to say that some of
the installations I have been called in to look at have made my hair
kinda' stand on end . It is amazing that more potters have not had
major catastrophies. It is a testament to constantly paying attention I
guess... 'cause too often the kiln installation is a disaster waiting to
happen.

One of the KEY factors for a difference in getting them installed you
already mentioned....... the involvement of the gas company ENGINEER.
Engineers have these nice little pieces of paper from prestigious
institutions that say they know what they are doing. And usually nice
little licenses from the state. "When EF Hutton talks...... people
listen." (Old TV commercial...sorry .)

In getting an installation approved, on occasion I have had to submit MY
plan drawings (done in a CAD program) to a local licensed engineer who
does NOTHING to them except put a nice little stamp on them... and then
the unit gets approved by the state or the town. Oh yeah... actually
he/she does do something...... charge a bunch of money to put the stamp on
there . Frustrating... but a fact of life.

Typically, an industrial unit is designed and built to meet the
various "codes" that DO exist for such units. And quite often there is an
official "engineering stamp of approval" on the installation from
someone.... which supplies the various parties involved with a scapegoat
for blame should it be "necessary" later. It is all about "CYA". And
the engineering degree that person holds is recognized as making the
person an "expert" .... even if they really don't know that much about
kilns specifically.

One thing to keep in mind is that as a craft potter... you NEVER want
anyone to attempt to apply those types of codes or refer to your kiln as
an "industrial furnace". That little terminology detail can bring the
wrath of inspectors and regulations down on you in a heartbeat. The giant
sucking sound you will hear is your wallet being cleaned out .

Most localles do not have ANY specific codes listing "potter's gas kiln"
or anything like that. That fact is the one you absolutely want to play
into. If there are no specific regs listed in the codes that the town
uses... then there is some room for you to "work" the situation....and
control the level of expense you'll end up with. "Wiggle room". Then YOU
can supply all the detailed information that they need to make a
decision. Do the presentation really slickly....and they will frequently
buy it.

I find that most potter's gas kilns are flirting with the absolute MINIMUM
compliance with the gas codes. Many are not within the code... but
someone often lets them get away with it. Many are older
installations ... that are sort of "grandfathered". Many are point blank
illegal. Industrial units typically have very sophisticated and expensive
controls and safety systems on them... that most potters would not be
willing to purchase.

The typical BASO and thermocouple flame safety that you see so often is
pretty low technology stuff... and can be bypassed VERY easily. One only
needs a brick or particularly a "C" clamp. And the response time to a
flameout is upwards of 30-40 seconds. And they don't have any interlocks
on stuff like the damper being open, make up air being open, pressures
being in the acceptable operating range, and so on. All of that kind of
stuff is pretty much an industrial standard.

For example, for kilns with burners running over 500,000 BTU total input
(even potter's kilns), units are typically required to have a double
automated valve block and bleed system on the supply side as part of the
flame safety system. This single part of the system takes three solenoid
or hydrostatic valves and the electronics to test their functionality on
startup, not to mention to operate them in the correct sequence on
proofing loss..... the two valves on the supply line close and then after
that happens the valve venting the gas line bleeds of the gas in it to an
exterior vent. Slick but expensive.

I have done installations where the flame safety and crap like that
involved has topped $1000 per burner just to get it thru the regulatory
practice (major city location). Luckily sometimes institutions can afford
that kind of thing.

Anyway... this is getting long and involved . If you are looking for
more info on kilns... I have done postings to CLAYART in great detail on
this whole subject many times in the past..... there should be a LOT of
kiln info in the archives. I really have been less active here on CLAYART
of late....... just too much to keep up with in life .


best,

............john

John Baymore
River Bend Pottery
22 Riverbend Way
Wilton, NH 03086 USA

JBaymore@compuserve.com
http://www.JohnBaymore.com

John Baymore on tue 21 sep 04


Gail,

"Houston, we have a problem."

I seem to remember reading your thread a while back as I skimmed CLAYART.

I think that there is a good possibility if you hand that document over to
your favorite "gas types".... you will likely get stopped in your tracks
before they read to the second page. It took me about 10 seconds just
starting to see exactly what that document you found said (professional
interest as a professional kiln builder/designer)....to see the "fly in
the ointment". Having put in hundreds of fuel kilns..... I have a concern
here with this document.

I have to go back there to the link you gave.... but is that document
sourced/intended for another country? That may be a factor in the
language used there.

In about the second paragraph it mentions the kiln shoud be "certified".
Currently the only craft potter type gas kiln in the USA that carries the
AGA certification are the beautifully done Geil units. Site built kilns
(at least craft potter types) are not typically AGA certified. I seem to
remember that you buiilt your kiln..... so it isn't likely "certified".

I haven't gotten further that that paragraph into the document yet... but
that is a real "red flag" in my book. One of the things I do when I am
working with a client is "work the approval process" as best we can to
minimize hassles and costs.... and this is NOT a document that I would
ever share for just that reason alone.

There is a lot of politics and human psychology at play in doing
permitting for kiln installations. When you put in a gas (or oil or wood)
kiln, the local people that you deal with almost for sure have NO CLUE
about what you are doing. But THEY are the ones that have to give an
appoval on it. When they put their "stamp" on the approval... they are
now taking on some political and legal liability. If perchance, your gas
kiln explodes and kills a neighbor........ THEY do not want anyone looking
at THEM for the invariable witch hunt for "who approved this thing to
start with?" So they are ALWAYS looking for some "out" to take the onus
or decision making off of their heads and place it on someone elses.

The American culture of litigation and contingency lawsuits drives a lot
of this unfortunate thinking. Also Americans general tendency to truly
believe that someone else must be responsible for just about everything
that happens to them. So the "powers that be" typically are VERY careful
when they are clearly "in over their heads". A "certification" "passes on
the buck" so that if something happens, they can in turn point a finger
elsewhere.

If they are looking for it.... and from your prior posting it seems they
are....... you will likley hand them the "out" that they are looking for
to get their own butts off the hook from putting any sort of "stamp of
approval" on your site built unit. But not the way you intend. They will
possibly say so sorry, your unit is not certified as it says it should be
right in the document you supplied....sorry....it is not OUR fault. Get
an AGA Certified unit and we'll gladly hook that up.

The only possible savior here is if you have a very positive "human to
human" relationship with those folks... and they "overlook" that little
detail. Which they COULD.......

The whole AGA certification thing that is looming its ugly head in the USA
is in danger of making it VERY difficult for potters to put in site built
kilns for any kind of reasonable cost. We will possibly soon end up with
a whole cadre of potters who.... as far as fuel kilns go... are "appliance
operators".

The Geil kilns are great units.... but they started a real issue for craft
potters in general when they went for the AGA Certification as basically a
marketing approach to give them strategic advantage over their competition.

All that being said... if I am remembering correctly your kiln has
multiple burners (6, I think?) that run with only a single
pilot/thermocouple/BASO system monitoring a single burner. Or maybe it
was two banks of three burners with a single pilot/thermocouple/BASO
monitoring one burner on each bank (center one). If that is true (and I
am not sure it IS here)... then that flame safety situation is VERY far
from the standards of practice of ANY current building or gas code that I
know of here in the USA. So that is a potential "thorn" in this thing too.

I see some "hope" in the fact that the gas company only wanted to see some
firing instructions rather than "calling" you on the flame safety setup
straight off. That might tell me you are "out in the boonies" where the
gas company can tend to be a bit "lax" on such stuff.

But that is also a warning that the gas company you are dealing with is
not really "watching" the installation well. Remember, if they are not...
YOU need to be. And while with care you can likely fire such a unit
without having any major issues....... you need to stay on YOUR toes with
that style of flame safety system.

That opinion is all worth exactly what you paid for it .

best,

..............john

John Baymore
River Bend Pottery
22 Riverbend Way
Wilton, NH 03086 USA

JBaymore@compuserve.com
http://www.JohnBaymore.com

John Rodgers on tue 21 sep 04


John Baymore wrote:

>Gail,
>
>"Houston, we have a problem."
>
>
>
John, your response to Gail's query is very informative. I have
ambitions to eventually build a Gas Fired kiln, and the increased
interest by "authorities" is possibly a problem to me in the future.

There are many big gas kilns in use in industry, and I wonder just how
"Certified" they really are.

In my own experience with industrial applications, though fairly light
(90-100 cubic foot car kilns), there were no certifications other than
that by the local electrical inspector and the local plumbing inspector
in combination with the gas company engineer. The building inspector
passed judgement on the structure that housed the kiln, but that was it.
Absolutely nobody knew anything about how a big gas kiln was supposed to
be operated. I think there was an assumption that if you had a kiln that
big, then surely you knew enough to operate it safely. Conjecture on my
part, but it sure seemed that way.

John Rodgers
Chelsea, AL