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(still) gaskiln questions & problems.

updated thu 13 jul 06

 

Lori Leary on sun 9 jul 06


Marianne,
Sounds like you might have too much fuel in your fuel/air mix. That can =
cause too much reduction and cause your kiln to stall. It also wastes fu=
el. The Olympic is an updraft, isn't it? How many cubic feet is it? W=
hat is your gas pressure? Can you reduce your fuel pressure and increase =
your primary air mix? What kind of burners are you using?=20
Best,
Lori L.

marianne kuiper milks wrote:

>I have a top-loading Olympic gaskiln: three regular tiers plus a 3" ring=
. Propane.
> We've done everything the good book said, installed and measured and pr=
essured everything..the works.
>
> These are my main problems for which I'd like to find solutions or sugg=
estions where to go from here.
>
> - The amount of soot blowing out of the tolp hole is frightening. About=
half goes up and out (properly done), the rest billows into my shed, ove=
r the correctly measured and installed stainless steel cone that feeds in=
to the triple tube.
> Can this be correct???
>
> -There is always a bunch of soot, in streaks, on the inner wall above t=
he 4 burners. All the way up. Is that normal?
>
> - I can often NOT get the temp to go above 1165=BA C, no matter how lon=
g I wait, fiddle or swear. But the ^5 starts going down at the lowest pee=
p, so I shut it off.
>
> -I am afraid that, in sp;ite of all precautions, I will burn the shed d=
own because the flame leaps beyond the cone (which is 8"=F8 larger than t=
he kiln).
>
> -The flame coming from the top hole can be from barely visible to 1.5' =
high.If I don't turn it up, eventually, the temp falls and nothing happen=
s to my pots.
>
> _A ^5/6 load takes me about 9-11 hours, sometimes longer. I leave it co=
oling overnight oruntil next afternoon.
>
> Can anyone give me reasons why the Olympic top-loading, 4 burner #...G =
produces so much smoke and soot?
>
> What can I do about it?
>
>
>
> Marianne Milks
>
>

Frank Colson on sun 9 jul 06


Marianne- In reading your description, my gut feeling is that you do not
have proper combustion occuring! Although I am unfamiliar with the specific
Olympic kiln you have, the principals of combustion are always the same, no
matter what kind or shape of kiln. What is the cubic size of your kiln?
There is a specific formula of gas to air ratio related to the cubic foot
size of the kiln. If this is incorrect, then forget it! Propane is a heavy
fuel and unless there is sufficient primary and secondary air (at the point
of burner input) for combustion ,the kiln will "choke" and all you are going
to get is excessive carbon and little heat! How many burners are on your
system? One big burnner can really mess up a firing unless there is some
"forced" air included!

One of the first kilns I ever built, a hundred cubic footer, had 32 small
(1" ID) burners with which I could drop cone 10 evenly from top to bottom.
from the first firing on. That was 5' high, by 5 wide!

Frank Colson

----- Original Message -----
From: "marianne kuiper milks"
To:
Sent: Sunday, July 09, 2006 6:02 PM
Subject: (still) gaskiln questions & problems.


>I have a top-loading Olympic gaskiln: three regular tiers plus a 3" ring.
>Propane.
> We've done everything the good book said, installed and measured and
> pressured everything..the works.
>
> These are my main problems for which I'd like to find solutions or
> suggestions where to go from here.
>
> - The amount of soot blowing out of the tolp hole is frightening. About
> half goes up and out (properly done), the rest billows into my shed, over
> the correctly measured and installed stainless steel cone that feeds into
> the triple tube.
> Can this be correct???
>
> -There is always a bunch of soot, in streaks, on the inner wall above the
> 4 burners. All the way up. Is that normal?
>
> - I can often NOT get the temp to go above 1165 C, no matter how long I
> wait, fiddle or swear. But the ^5 starts going down at the lowest peep, so
> I shut it off.
>
> -I am afraid that, in sp;ite of all precautions, I will burn the shed down
> because the flame leaps beyond the cone (which is 8" larger than the
> kiln).
>
> -The flame coming from the top hole can be from barely visible to 1.5'
> high.If I don't turn it up, eventually, the temp falls and nothing happens
> to my pots.
>
> _A ^5/6 load takes me about 9-11 hours, sometimes longer. I leave it
> cooling overnight oruntil next afternoon.
>
> Can anyone give me reasons why the Olympic top-loading, 4 burner #...G
> produces so much smoke and soot?
>
> What can I do about it?
>
> I now have nicer results and much testing. That isn';t so much the
> problem. i'm now concerned about fire, health and my husband's nearby
> Miata.
> I did have 2 professional potters, both friends and college professors,
> very familiar with all sort of huge kilns to look at it. They both
> scratched their head, said they'd never seen a kiln like this and wished
> me luck.
> I like luck, but I prefer solid knowledge.
>
> If you have any ideas to help, please tell me.
>
> Marianne Milks
>
>
>
> ---------------------------------
> Talk is cheap. Use Yahoo! Messenger to make PC-to-Phone calls. Great
> rates starting at 1/min.
>
> ______________________________________________________________________________
> 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.
>

Mark Issenberg on sun 9 jul 06


I also had one of those Olympic gas kilns years ago.. I hated it..I would
really like to tell how i really felt about Olympic gas kilns but i wont. What
i think you need to do is call Olympic and ask them to help you with the
problem you are having.. You should post your answer here for all of us to read
and all the help they give you..

Mark

marianne kuiper milks on sun 9 jul 06


I have a top-loading Olympic gaskiln: three regular tiers plus a 3" ring. Propane.
We've done everything the good book said, installed and measured and pressured everything..the works.

These are my main problems for which I'd like to find solutions or suggestions where to go from here.

- The amount of soot blowing out of the tolp hole is frightening. About half goes up and out (properly done), the rest billows into my shed, over the correctly measured and installed stainless steel cone that feeds into the triple tube.
Can this be correct???

-There is always a bunch of soot, in streaks, on the inner wall above the 4 burners. All the way up. Is that normal?

- I can often NOT get the temp to go above 1165 C, no matter how long I wait, fiddle or swear. But the ^5 starts going down at the lowest peep, so I shut it off.

-I am afraid that, in sp;ite of all precautions, I will burn the shed down because the flame leaps beyond the cone (which is 8" larger than the kiln).

-The flame coming from the top hole can be from barely visible to 1.5' high.If I don't turn it up, eventually, the temp falls and nothing happens to my pots.

_A ^5/6 load takes me about 9-11 hours, sometimes longer. I leave it cooling overnight oruntil next afternoon.

Can anyone give me reasons why the Olympic top-loading, 4 burner #...G produces so much smoke and soot?

What can I do about it?

I now have nicer results and much testing. That isn';t so much the problem. i'm now concerned about fire, health and my husband's nearby Miata.
I did have 2 professional potters, both friends and college professors, very familiar with all sort of huge kilns to look at it. They both scratched their head, said they'd never seen a kiln like this and wished me luck.
I like luck, but I prefer solid knowledge.

If you have any ideas to help, please tell me.

Marianne Milks



---------------------------------
Talk is cheap. Use Yahoo! Messenger to make PC-to-Phone calls. Great rates starting at 1/min.

Randy McCall on mon 10 jul 06


Marianne

I have a 12 cu ft Olympic with 4 burners and have fired it about 15 times or
so. The only problem I have had has been the difference in cones between
the top and bottom. I have gotten some suggestions on how to fix that but
have not tried them yet as I have been firing in my electric.

My Olympic actually will fire too quickly and does most of it in oxidation.

One thing I would check is the burners and the orifice opening. Are you
sure that the burners are for propane and not natural gas? A gas company
can check the measurements. If you can get one out take it too them. Also
if you bought this used someone may have bored them out for some reason. If
you can't get them out find out what the proper measurement would be and
find a wire of the same measurement or see if you can get them to loan you
there tool for checking orifice openings.

I also use a 100lb tank and have problems with it freezing at times if it
gets too low on gas.

Another thing make sure that the burners are below the openings so they
have plenty of air. Do not allow them to be sticking inside the openings.
Probably need to try to make sure the burners are about 1/2 inch below the
opening at first and then adjust. I had to use iron shims to lower the
burners.

You may want to take it apart and just check to see how the burners burn
without the kiln on top. It only takes a few minutes for two people to move
the rings off the burners.

There are some good suggestions on ClayArt in the past 2 years on getting an
even temp from top to bottom.


Randy
South Carolina
Pottery Web site

http://members.tripod.com/~McCallJ/index.html

Ben Shelton on mon 10 jul 06


As stated by others, combustion principles are universal and you have an
improper fuel/air ratio. You either have too much fuel or too little air.

I will assume that these burners are venturi types (no fan motor). If so
they my have the wrong size gas orifice or they may have some blockage
preventing good air flow to mix with the gas. Propane is stored at higher
pressure than natural gas is supplied so you need a smaller opening with
propane to get the same oerall volume of gas flow. You will have to remove
one of the burners to check the orifice size and you will have to check
around to find out what the proper size orifice is for each type of gas. My
memory fails me. The kiln book or maybe Ward burners website might be good
resources.

If these burners were supplied with orifices for natural gas by error then
the kiln will fire very rich.

Alternately, if you are not getting enough air... Try opening the primary
air shutters on the burners(if venturi). Check to see that some critter
hasn't blocked the passages with debris such as nests/webs.

I like the theorythat you got natural gas orifices and are using propane
thus the problem.

Let us know what the result is, we're curious how it turns out.

Ben

Brian Fistler on mon 10 jul 06


Are you SURE the kiln is set up for propane?

The orfice size for propane is MUCH smaller than for natural gas.

If the orfices in the burners are set up for natural gas, you would be
dumping WAY too much propane into the kiln, hence yellow flame even with
the air inlets fully open.

Brian

Frank Colson on mon 10 jul 06


I concur!

Frank Colson
----- Original Message -----
From: "Brian Fistler"
To:
Sent: Monday, July 10, 2006 6:41 AM
Subject: Re: (still) gaskiln questions & problems.


> Are you SURE the kiln is set up for propane?
>
> The orfice size for propane is MUCH smaller than for natural gas.
>
> If the orfices in the burners are set up for natural gas, you would be
> dumping WAY too much propane into the kiln, hence yellow flame even with
> the air inlets fully open.
>
> Brian
>
> ______________________________________________________________________________
> 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.
>

Ivor and Olive Lewis on tue 11 jul 06


Dear Marianne,=20

There is only one answer to your question <<...Can anyone give me =
reasons why the Olympic top-loading, 4 burner #...G produces so much =
smoke and soot?...>

The simple answer is that the gas to air ratios are up the creek. Too =
much gas, insufficient air...
=20

<<...What can I do about it?...>>

Have the Gas Jets checked. These must be chosen to match the nature of =
the gas you are using. The gas jets must be sized to match the type of =
gas you are using and the amount of Primary air that you can admit into =
the mixing chamber of the burner. It also sounds as though you are =
unable to admit a sufficient volume of secondary air into the kiln to =
complete the burning operation.

This is a task for a qualified Gas Engineer. The name "Mark Ward" =
springs to mind.

Smoke and Soot are a sign of inefficient burning and profit going up the =
chimney.

Best regards,

Ivor Lewis.
Redhill,
South Australia.


By the way, can we have a private conversation about symbols on some =
music I am looking at? I recall you are a High Class Muso=20

marianne kuiper milks on wed 12 jul 06


Dear Ivor,

Thank you, too for your imput. There are a few problems with all the answers I have been sent, and there is a common thread as well.
I HAVE the right burners: they were (after questionaire) sent by Olympic and checked by my professor/friend. Our gasman/plummer has installed many of these devices on area kilns. His brother is a potter and he has many customers here (Poconos are a bee's-nest for artists: all for the honey!)
I Do believe that the distance to the kiln is wrong: all but one burner are too close. The WHOLE kiln also is not full of soot: just on the walls of two opposite burners. The soot that comes billowing out the top is another matter. Carl says I act really funny after each fining. (Just kidding)
I will have the air pressure/water column checked again, but i do believe I had an issue with the gas co on that: they insisted on 15. I believe (they said...) I got my way.

Everything will be re-checked by Carl and myself this coming weekend, with several high-blast, quick firings to see what happens. i will let you(all) know.

I SO appreciate everyone's time. I have a (fire)ball with that kiln!

Thanks! And the answer on the other issue is yes, of course.

Marianne

Ivor and Olive Lewis wrote: Dear Marianne,

There is only one answer to your question <<...Can anyone give me reasons why the Olympic top-loading, 4 burner #...G produces so much smoke and soot?...>

The simple answer is that the gas to air ratios are up the creek. Too much gas, insufficient air...


<<...What can I do about it?...>>

Have the Gas Jets checked. These must be chosen to match the nature of the gas you are using. The gas jets must be sized to match the type of gas you are using and the amount of Primary air that you can admit into the mixing chamber of the burner. It also sounds as though you are unable to admit a sufficient volume of secondary air into the kiln to complete the burning operation.

This is a task for a qualified Gas Engineer. The name "Mark Ward" springs to mind.

Smoke and Soot are a sign of inefficient burning and profit going up the chimney.

Best regards,

Ivor Lewis.
Redhill,
South Australia.


By the way, can we have a private conversation about symbols on some music I am looking at? I recall you are a High Class Muso

______________________________________________________________________________
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.



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