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Wiley 10-12-2008 08:26 PM

Panting oven
 
Tonite for the second time I have had my oven "pant". Unfortunately I didn't have a big enough card in my camera to record the video and by the time I installed the 4 gig card it had stopped but I now know the "setting" of the draft door and hopefully can replicate the "pant". Had anyone else experienced their oven panting?

OK, for those unfamiliar with the term "pant".... one can see it in movies of old steam locomotives when they are laboring for instance going up a grade. The chimney puffs smoke at intervals and in the cab the stoker door has a momentary back blast of exhaust followed by an intake or inhale. The stack/chimney has a blast of smoke followed by a pause then another blast. The period of the pant varies but my oven pants at about every second or slightly less. Quite cool looking but I'm not sure it is good for an oven. On my oven it is not so evident in the exhaust from the chimney but there is an audible puff and with it a short blast of smoke out the slot in the draft door followed by and intake of all the expelled smoke which is followed shortly by another out blast. The smoke puffed out the slot in the draft door is sucked back into the oven and then the process is repeated. This went on long enough for me to decide that I should be recording it and run for a camera. By the time I had finished messing about with the new card etc. it had stopped.

Honest, I didn't have anything to drink (yet) and only the oven was smoking!

Bests,
Wiley

Les 10-12-2008 08:32 PM

Re: Panting oven
 
Wiley - I haven't seen that. Mine just seems to be an even flow. Are you making the fires of hell? It does sound like a fun thing to watch!.

Les...

Wiley 10-12-2008 08:56 PM

Re: Panting oven
 
Quite the contrary, I'm not one of those who want to see the Fires of Hades. I've seen ovens that were burned up, I don't care to build it twice.

It happened just after the fire caught and starting to go well, and once the oven got hot the panting stopped. We had neighbors over for pizza and the Mister said that he used to have that happen often when he had wood fired ceramic ovens. He said his ovens used to back blast out 4 inches (while mine was barely an inch or an inch and a half). He said it happened in his oven when the atmosphere in the oven was switching from a reducing atmosphere to an oxidizing one (ie not enough oxygen to too much (or sufficient) oxygen. But what do I know? He might be feeding me a line although he used to make his living from pottery.
Wiley

arevalo53anos 10-13-2008 06:16 AM

Re: Panting oven
 
I have never seen that!
Just a shot...figuring out...
If the relationship between the heights of door and dome is lower than 63%, there be not fully combusted gases on top of the inner dome, because the incoming fresh gases are ‘sealing’ the exhaust gases path.
When the top of the inner dome reach the temperature to burn these ‘not fully combusted’ gases, the higher pressure produced by these gases combustion, push them through the door, stopping the exhaustion of fresh air. From there you could see a black smoke going out of the oven door.
With the dome gases fully combusted, the inner top is ‘empty’ and ‘cool’ how to receive ‘rare’ gases again and the cycle continues...
In short, in a well-balanced dome-door oven, the fresh air enters by the ‘lower half door space’, ignited on the hearth, fluxing combusted on flames through the dome and exhausted by the ‘higher half door space’.
Is there any sense?

Luis

egalecki 10-13-2008 07:12 AM

Re: Panting oven
 
Quote:

Originally Posted by arevalo53anos (Post 42654)
With the dome gases fully combusted, the inner top is ‘empty’ and ‘cool’ how to receive ‘rare’ gases again and the cycle continues...
In short, in a well-balanced dome-door oven, the fresh air enters by the ‘lower half door space’, ignited on the hearth, fluxing combusted on flames through the dome and exhausted by the ‘higher half door space’.
Is there any sense?

Luis

Makes a lot of sense to me. The panting must have been pretty cool in a kind of worrying way!

Wiley 05-22-2009 09:29 AM

Re: Panting oven
 
OK, like the saying goes: "I might not be good, but I am slow".... I have finally captured and uploaded a video of my oven panting. In the usual firing the period of the panting lasts only a few minutes and the period (cycle) of the pant can be slightly adjusted by moving the draft door in or out.

In order to get this video I built a smaller fire and so the pant lasted longer as the oven took longer to heat. I couldn't see more than a slight variance of smoke out the chimney top with each pant. I suppose one could build a chimney stack shaped like on an old time steam locomotive (cone with restriction at top) where the smoke collected momentarily. However, I think it would look pretty strange on my WFO. For those curious to see the pant, here's the link:

YouTube - Panting Wood Fired Oven

Wiley

brickie in oz 05-22-2009 03:14 PM

Re: Panting oven
 
That is so cool.....:cool:

PizzaPolice 05-22-2009 05:07 PM

Re: Panting oven
 
Cool my A$$! Son, you have the makings of a back draft! DO NOT try to replicate that.

brickie in oz 05-22-2009 05:16 PM

Re: Panting oven
 
Quote:

Originally Posted by PizzaPolice (Post 56079)
Cool my A$$! Son, you have the makings of a back draft! DO NOT try to replicate that.

Settle down.....:p :rolleyes:

texassourdough 05-22-2009 06:18 PM

Re: Panting oven
 
It looks like your door is too small for your oven volume and you are addumulating unburned gases which .... burn and create the pant.

Wierd!
Jay


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