How Long To Allow Fire To Burn

[foodnelson]

I am new to this site. I just installed my Primavera 70 and I let it sit for a week. I now have to light the first curing fire and I have a question. I was told by a employee and Forno Bravo to let each fire during the curing process burn for 6 hours. However, a lot of people on this blog recommend you only burn the curing fires until the oven reaches temp and then shut the door and let the fire burn out. Which is it? 6 hours at temp or just bring the oven to temp and close off the oven and let the oven cool down?

Also, what material did you use to do your first 200 degree burn and how many times did you have to feed the fire until it got to temperature?

Thank you in advance for your advice.

[applor]

Re: How Long To Allow Fire To Burn

bring it to temp, making sure it does not get any hotter and then keep it going as long as you can (longer the better).

[SableSprings]

Re: How Long To Allow Fire To Burn

The forum link below begins with a thread on oven curing. It's got a great explanation of temps and suggested materials to burn.

Firing Your Oven - Forno Bravo Forum: The Wood-Fired Oven Community

As noted by applor and by James in the curing thread linked above, the important thing is to build your temps up very gradually and hold at each +100F level increase for as long as you can. It's really helpful to have the IR gun to monitor temps...if you don't, follow the suggested fuel amounts in the schedule.

So using just paper and a few sticks of kindling for the 300F level (second day) means start the fire and let it almost burn out, then add about the same amount of twigs, again & again ( until the beer runs out ). You'll get the oven up to about 300F and it will maintain as you keep adding small amounts of the scheduled "fuel". On the third day, you'll light up a slightly bigger piece of dry wood (with a little paper) and as it burns down to coals, add one more piece of similar sized wood...watch the size of the fire at each temp stage/level and don't let it get bigger...just add to maintain ( again, until the beer runs out ). The week will pass quickly and you'll be making pizza in no time...relax and enjoy the experience!

[foodnelson]

Re: How Long To Allow Fire To Burn

My first burn is over and I got it to temp but it did spike a few times. If the oven gets to hot on the first burn will it crack? How long until you notice the cracks if it is going to crack.

[SableSprings]

Re: How Long To Allow Fire To Burn

If you don't ignore the firing instructions for the curing day, temperature spikes are short and shallow (as far as the bricks & mortar are concerned). A piece of wood may burn a little hotter than another...no problem...it's the concept of not overfiring. Again, the mantra is low and slow. You need to SLOWLY drive that moisture out of the oven structure, so getting the oven up to temp for each level is simply moving the moisture consistently outward. Each day, with the bump in temp, you're pushing the moisture a little farther out and drying the oven & insulation just a little bit more.

Even if the curing is done slowly and correctly, as the oven bricks and mortar dry, cracks may appear where there are structural or construction material problems/defects. Forno Bravo kits have been pretty well designed and use high quality components. Yes, there have been cracks in kit plates during curing or use...but from everything I've read on this forum these problems are normally minor and if it's a real problem, they stand behind their product and will work with you to get it fixed to your satisfaction.

Most often, if you are going to get a crack, it will appear towards the end of the curing process, or after a particularly hot fire before the refractory material is fully cured. Understand that a few small cracks do not mean the oven is a failure. Many of us have years of great pizza parties and bread bakes under our belts with cracks in our ovens (both purchased and home built). In fact, there are many bakers who judge the oven's heat saturation level by the width/size of oven cracks. There is an old saying among masons and folks who work with cement products: "There are two types of concrete: the kind that has cracked and the kind that will crack." My personal opinion is that a similar saying should exist for masonry & cobb ovens

again...Relax and enjoy the experience!

[foodnelson]

Re: How Long To Allow Fire To Burn

Mike,

Thank you very much. I am going to get a lot more beer for tomorrows burn and enjoy the day!