Gas fired Pompeii Oven?

[DaveHI]

voodoo. yup.
Having a leak in a gas line/hookup INDOORS such that it fills a restaurant and gets set off by a refridge some distance away is a large volume of gas. Whether said leak came from a pizza oven or a regular stove or a space heater or whatever is rather a pointless distinction. The problem is a gas leak with a large enough space to build up enough gas to have a powerful explosion.
Unless someone can point to a calculation that says a 40 inch domed oven is truly a risk or to a case where someone actually did some damage outdoors, I don't think I'll sweat my installation much. No different than a grill.
Install/use a shutoff valve, leave the door out, use your nose (brain).........pretty safe.

Wonder what the volume of expansion of a gallon of water getting dumped in a WFO from a failure of a pot would do ;>) ................... I seem to recall 1000:1 ratio of steam to water.
like this dimwit
https://www.youtube.com/watch?v=XCCDxneNG3A

[Toomulla]

This discussion has a touch of the voodoo, if you want a gas installation get it done by a licensed professional and it will be as safe as any other gas installation, Gas is used for millions of heating installations and anyone can find examples of explosion etc resulting from poor installation. Personally I have a WFO because I enjoy the process, but can acknowledge that others may want or need otherwise,Perhaps some guidance on how to get it done safely would not go astray.

[deejayoh]

Good points Russell

One doesn't have to search too far in the google machine to find tragedies caused by this (though it's unclear if this was a brick oven or just an oven)

"An investigation found that the gas leading to a pizza oven had been left on overnight and was ignited by a spark from a refrigerator inside the restaurant"

http://www.arabianbusiness.com/deadl...l#.V8x7ppgrKUk

I do think our hosts should make their position on this clear.

[UtahBeehiver]

Mexman,

Your point taken, but as you noted, you friend installed a $35 gas burner, created a bomb and this is the issue that is at hand. I come from the natural gas industry, well over 40 years and I fully understand what happens when the well intentioned, but uninformed or novice, attempt gas installations without proper training, certifications, engineering, and safety processes when dealing with natural gas, propane or any hydrocarbon fuels. I have no problem using natural gas (paid the mortgage), but as David said, safety shutoff valves and more importantly proper installation by a certified process or installer is critical. Yes, FB now sells natural gas conversions, with certain caveats and they have also procured all the safety certifications necessary for a UL listing and installation. I am sure some builders are fully capable of installing natural gas burners but there are certainly those who should leave this to the professionals. The penalty for screwing up is someone getting hurt.

[Mexman]

Every forum has a few Naysayers that don't have all the facts and say things that are not 100% accurate.
I have a friend who converted his WFO to gas with a $35 gas burner and I've told him he has created a bomb.
I spent over $1200 for a commercial burner (Drago) with safety shut offs. They have installed several thousands of them with no problems.

[david s]

It can be quite dangerous and that is why the forum administrators have asked members not to discuss the use of gas on this forum. Take the scenario of someone who fits a home made gas burner or adapts one that is not designed for this purpose and the burner does not have a flame failure device.if the oven is hot and also contains some burning wood, filling the chamber with unignited gas will have explosive results.

I think the request from the forum admin was about 8 years ago. Many of the posts on the topic, mine included , have been deleted.Some clarification from admin would be welcome.

[deejayoh]

I've never seen a post from forum administrators that indicate you should not talk about gas. Especially, since they sell them.
There are thousands of gas ovens in operation at pizza parlors across the world. Hardly any have ever blown up.
California Pizza has converted all their WFO to gas.

Also - FWIW - I think if there really is a prohibition on talking about gas fueled ovens - the administrators should have it clearly posted in the forum guidelines. I looked, and don't find anything in any of the stickies that mentions gas-fired ovens in any way. The only prohibition is commercial content.

[deejayoh]

That avanzini burner is a $1,000, purpose built gas burner for a pizza oven. I'm thinking they might have one or two safety features on it. I'd consider adding one if I could get gas the back of my oven - but I built on a retaining wall so don't really have access without a lot of messy digging. Next oven might be dual fuel though.

Drago is fully automatic and does everything itself. Other burners have a pilot flame that is lit manually with a piezoelectric lighter like a barbecue oven and, if the flame is accidentally extinguished, take over 25 seconds to shut off the gas, whereas Drago takes 3 seconds at the most. Drago is also the only burner that, in the event of poor combustion caused for example by a poor draught, in order to avoid possible hazards, shuts down and warns the pizza maker that there is something wrong.

[Mexman]

I've never seen a post from forum administrators that indicate you should not talk about gas. Especially, since they sell them.
There are thousands of gas ovens in operation at pizza parlors across the world. Hardly any have ever blown up.
California Pizza has converted all their WFO to gas.

[david s]

It can be quite dangerous and that is why the forum administrators have asked members not to discuss the use of gas on this forum. Take the scenario of someone who fits a home made gas burner or adapts one that is not designed for this purpose and the burner does not have a flame failure device.if the oven is hot and also contains some burning wood, filling the chamber with unignited gas will have explosive results.

[DaveHI]

It's doable. Works fine. I've only used mine twice so far so not sure if the slow heatup is still a curing issue or just less overall btu input. The Avanzini burner is 52,000 Btu/hr if I converted correctly. That's only about 10 lbs of wood. When I fired my WFO in Hawaii I'd jam in twice that much wood and have a raging fire during startup.

That said, the gas is soooooooooooo easy. Push a button, heat appears. No ash etc etc. I'd still use wood but in SOCAL in tight neighborhoods no can do due to HOA rules. so it was gas or nothing. I went with nat gas as right now it's very cheap and I hate haulling propane cylinders.

I get the oven to about 750 dome/550 floor in 45 min of full firing. After an hour of cooking, was more like 850 done and 625 floor. I thought cooking was painfully slow - 3 to 4 min vs. 2 min in a hot oven fired with ironwood. Crust got nice and crunchy and my critics backed off toward the end when the temps got higher. Just can't please some people ;>).

I suspect the gas burner would do better in a pre-cast oven with so much less mass to heat up. I built a 37 inch (ish) Pompeii with full half brick thickness. In 20/20 hindsight might should have backed down to 1/3 brick thick.

Installation was a breeze -- since I had a licensed plumber do it. Same guy put in the gas line. The cost of the burner and line were about 2X the cost of the Pompeii oven itself. But it was that or nothing. Took him a couple of hours to hook it up, but that included a store run. I wanted to make damn sure the install met code so I didn't chance doing it myself. I had him install a block valve upstream of the controls to make extra sure of no leaks. And a second block near the meter for when I don't plan to use it for a while. Gas downstream of the meter is at such low pressure, double block is pretty much certain to be overkill but valves are cheap.

Still don't understand why people are so nervous about a gas bubble anyway. I calculated the volume of gas above the entry arch at about 0.9 ft3 with the energy value of maybe 3-4 tablespoons of gasoline (1000 btu/scf for methane roughly and maybe 120,000 btu in a gallon of gasoline). And since you need 5- 15% methane to get an expolsive mixture, even that's high buy 10X.. Maybe you could trap more gas with a door in place, but it's still not a big volume of gas. I think you'd have to be pretty stupid to do much damage -- dome completely full of 15% methane, no nose to smell gas, make a spark with your door or some such ...........still it's not much real energy in that small volume of gas/air. Propane could be scary if you found a way to get liquids trapped maybe.

[Mexman]

Cannot understand why more people are talking about firing with gas

[Mexman]

Propane
Natural gas is not advailable in my area

[deejayoh]

Mexman - natural gas or propane?

[Mexman]

I forgot to add , another plus to using gas over wood is temperature control. I can change the temp of my oven buy Turing a knob. Of course I have to wait unten the oven adjust.
I've found that my oven works best for me at 800 degrees. With gas, I can always be at exactly 800