Coal fired brick pizza oven

Well, I am a bit embarassed, this will be my second attempt at building a "Coal" fired brick pizza oven, never know I was born in the coalpits.... anyway after a substancial sum spent on this project, please note: http;//coalpeppers.com I fired up the old furnace, the pot and grates intact, surrounded by fire brick, 8" of insulation and covered in stucco, approx. size, well dome is about eight ft high, base is 7'x7' rounded of course, purchased special 1" thick pizza stones, blah, blah blah, firesd the old oven up with "Stove" coal, burning well, but the pizza oven cavity has to get to 900 degrees, barely reaches 150???? Ouch? (Did not place the last 8" chimney on yet, so the chimney is only aprox. 6" over roof level, doubt that that is the problem??? Anyway this old furnace heated an entire house and all Iwant it to do is heat a cavit approx. 200 cubic feet.

Anyway I open in two weeks, would be nice iof I could cook pizza??? Appreciate any and all assistance, really and truly apprecaite it.. and all the pizza you can eat...

tx.

Nick

I moved this to the hand fired forum.

Any pictures? that might help, having said that not many here are going to know how a pizza oven is supposed to operate.

Hi coalpits, Nick, welcome to the forum. I have a buddy, Larry, that built a wood fired outdoor pizza oven and he was telling me how he was going to convert his oven to fire anthracite coal. I'll have to see if I can get some pictures of his oven. All I know is that his oven makes some of the finest tasting pizza I've ever eaten! It would help if you could post some pictures for us. That way you may get some help. There is a vast wealth of knowledge here on this forum. I'm sure we could try to help you figure it out. DOUG

My first thought is the draft. What is the stack temperature? If you have a good fire going and getting 150*, there is some serious heat going somewhere. Is there a barometric damper in the stovepipe/chimney?

It wouldn't hurt to post some pictures of this beast, we love pictures and it may offer up some clues to what is going on.

900 degrees

Why so hot? I don't know about cooking in one of these ovens but that seems a few hundred degrees too hot.
Photos would be good but a drawing/diagram with dimensions etc. might help us understand the oven design better.

900ºF is perfect for cooking pizza. i've been to some of the new york pizza ovens fired by anthracite (i prefer grimaldi's under the brooklyn bridge) and i've been sure to check out their ovens. some pictures would be helpful. bear in mind that it's going to take some time to heat all that masonry up to that temp. if i saw some pictures i might be able to offer some advice about your situation, btw welcome to the forum.

Berlin wrote:bear in mind that it's going to take some time to heat all that masonry up to that temp.

Depending on the size of the mass, it could possibly take a few days.

Heres my 2 cents. been building one for a few years now. http://www.fornobravo.com/

coaledsweat wrote:Depending on the size of the mass, it could possibly take a few days.

My initial thoughts exactly. Assuming the draft is ok.
Still need Pics!

Hi Everyone,

Sorry about being so late in replying and thanking all of you for your help, in regard to pictures of the coal fired brick oven, well it took me a bit but here goes:

http://71.18.88.50/oven/front.jpg

http://71.18.88.50/oven/ashgrate.jpg

http://71.18.88.50/oven/ashgratemodel.jpg

http://71.18.88.50/oven/backcoalcenter.jpg

ttp://71.18.88.50/oven/backcoalload.jpg

http://71.18.88.50/oven/backcoalright.jpg

http://71.18.88.50/oven/chimneyback.jpg

http://71.18.88.50/oven/chimneyside.jpg

http://71.18.88.50/oven/frontcenter.jpg

http://71.18.88.50/oven/innerfrontcenter.jpg

http://71.18.88.50/oven/innerfrontleft.jpg

http://71.18.88.50/oven/innerfrontright.jpg

http://71.18.88.50/oven/ovenback.jpg

http://71.18.88.50/oven/ovenside.jpg

Okay! A coal fired pizza oven looks neat. Now for my observations, I noticed that for one, your chimney pipe is single wall and your barometric draft regulator should be balancing the pressure difference between the outside and the inside of the building. The way you currently have it arranged, the chimney pipe will cool fast, reducing draft, and the barometric won't balance the pressure, just some possible down drafts. It seems to me that your chimney is the problem. When using coal, balancing the draft is the key to a great fire.

I bet if you fired wood in there, it fires pretty well and can be regulated by how much fuel you put in it. Then again!,

Another thing to consider, is the kitchen hood. You may be sucking just enough air though it to prevent the chimney from doing it's job. That is where make-up return air comes in. Either for the kitchen hood or the pizza oven. You may have to get some fresh return air into the kitchen for the hood to pull from instead of the pizza oven.

That is my thoughts from seeing your pictures. I hope I helped. Feel free to discuss any issues that we may have not seen from the pictures. DOUG

my thoughts: oven arch is too high, chimney needs to be straight up for that short of a run and the baro damper needs to be changed to a lower position; also, and perhaps most importantly, where the smoke pipe is attatched to the inside of the oven should be at most only a few inches higher than the pizza loading door, not at the top of the oven arch (i didn't see where it was connected, but this will make a substantial difference in performance).

Good morning gentlemen,

Thanks for all the advice, first thingis I will make the stove pipe straight up, get rid of the elbow. I also will place the Baromatic damper lower towards the furnace cavity, once complete I wil let you know if that helped.

In regard to the dome/furnace being to high, not much I can do about that now, kind of stuck with the design...

The opening of the oven is inside the dining area, keep in mind this is a commercial restaurant, placed in this area for maximum exposure, people love watching you bake pizzas especially in a brick oven. It is doubtful with ten ft cielings we would not have enough combustion. Also the furnace itself has a air intake above the ash pan and this is located outside.

I also am looking into a "Draft Inducer" and placing it on the chimney, does anyone have any experience with Draft Inducers?

Thanks everyone,

Coalpit..

Now for the biggest question of all?? Where is the resturant? Any free samples for forum members?

Since this is a commercial operation you really need to know this thing you have created inside and out. I would get a manometer and a couple of thermometers for the stack (before and after the baro) so you know exactly what is going on with it. Once you establish some information about its operation, you will learn what it likes and dislikes and be able to operate it in a confident manner. You don't want that thing catching you with your pants down, it is after all the center of attention there.

As far as the install, like the others have said, the chimney may need some work. If needed, a double wall insulated chimney that was a lot taller and straighter would produce more draft. A draft inducer would also, but when the power is out for days, it might be sweet being the only game in town. I would go with the chimney. One last thing. Is the outside of that beast well insulated or is it giving up a lot of heat to the parking lot?

Berlin's comment about the height of the stack's intake may be the most critical component here, it makes a lot of sense with the design. It would almost act as a bypass damper increasing residence time.