Go Back   Forno Bravo Forum: The Wood-Fired Oven Community > Pizza Oven Design and Installation > Getting Started

Like Tree2Likes

Reply
 
LinkBack Thread Tools Display Modes
  #11  
Old 08-10-2012, 04:19 AM
Laborer
 
Join Date: Jun 2012
Location: London, UK
Posts: 90
Default Re: Thermocouple and insulated door for oven

That was one worry I had/have - the accuracy of the readings...

I'll pop 2 TC's in or so for now... and see what happens. Cheaper to spend a pound or two now and put them in than regret it later

M.
Reply With Quote
  #12  
Old 08-10-2012, 04:38 AM
david s's Avatar
Il Pizzaiolo
 
Join Date: Mar 2007
Location: Townsville, Nth Queensland,Australia
Posts: 4,880
Default Re: Thermocouple and insulated door for oven

Thermocouples and their readiuts inevitably fail, you need to make their replacement easy when you install them. When cooking pizza you don't need a temp indicator to tell you the pizzas are cooking too slow and therefore the oven temp has dropped off. When baking and roasting a cheap oven thermometer placed inside the oven is a simple and accurate instrument, that doesn't require, drilling, wires, batteries or high cost. I've got a couple of thermocouples but don't use them in my oven any more. If you are keen to spend money get a laser thermo.
Reply With Quote
  #13  
Old 08-28-2012, 03:02 PM
Journeyman
 
Join Date: Mar 2011
Location: Bucks County, PA
Posts: 297
Default Re: Thermocouple and insulated door for oven

I wrestled with the idea of using thermocouples....I am SO glad I did not use them. Instead, I simply bought a IR thermometer and take readings on walls and floor. You quickly get to know your oven and get a feel for the temperature inside just a few firings.

My opinion: don't waste your time with thermocouples. It only complicates your build and puts un-necessary holes in your oven. Buy a IR thermometer ($50) instead...you will have more data than you will know what to do with...just my humble opinion.
Reply With Quote
  #14  
Old 08-28-2012, 04:17 PM
WJW WJW is offline
Journeyman
 
Join Date: Jan 2012
Location: Camarillo, CA
Posts: 387
Default Re: Thermocouple and insulated door for oven

You know what they say about opinions...

I've got one too.

I did put thermocouples in my oven. Four of them to be precise. I am extremely happy I did so. I bake in mine, and I use it for retained heat cooking. If I were only using the oven for pizza, I would agree that they would be a waste of money. (BTW, mine cost forty bucks each). But having the thermocouples is very, very helpful for baking. They give me info that is impossible to get with an IR thermometer. (I have one of those too and agree that you need one.)

The thermocouples tell me exactly how saturated the masonry of my oven is because I have them embedded in different areas, and more importantly, at varying depths/distances from the interior of the oven.

Of the two in the hearth...one is between the firebrick and the insulation, so it is measuring the saturation of the brick at the farthest point from the hot oven interior. The other is mounted in one of the hearth firebricks which was drilled just over halfway through the brick going up toward the oven interior. So it is embedded in brick about an inch from the hot interior.

Of the two thermocouples in the roof arch, I did basically the same thing...one as far from the hot interior as possible where the insulation starts...one drilled into the brick an inch from the flames.

There is no doubt I could bake without them. I could simply build a very big fire in the oven and let it burn for four hours or so. I would know from experience that, after mopping out the oven and closing it up to allow it to equalize/cool for around two hours, my interior hotface brick would be around 600 and that it would cool down very slowly from that point due to the energy stored in the bricks. But there would be a lot of guesswork and I'd have significantly variable results from bake to bake. Not a good thing.

But with the thermocouples I know the exact temperature of the deepest levels of masonry. I usually try to time it so that I pull the fire out of the oven when the deeplest levels of masonry are around 625-650. In order to do that I start tapering off the wood when the deep layers get to around 590. By the time that happens, the interior of the oven has long since dropped from it's peak temp of 900 to 1000 degrees and now is dropping into the 700 range.

When the deep masonry layers get to around 625-650 I start raking the dying coals out and mopping out the oven. By the time I'm done doing that, the interior hotface bricks are around 550 degrees (after mopping/cooling/equalizing), and the deepest levels of masonry are still 650 degrees. I then close the door and let the interior come back up to around 590 or so before I put the loaves in.

I am then completely saturated and even as I put multiple batches of bread in, the oven cools very slowly from around 590 to about 500 over the course of four batches of bread. If I'm doing fewer batches, I don't let the deep masonry levels get above 600.

And, since every fire is different, I don't have to guess when I reach the correct point. By checking the thermocouple temps every thirty minutes or so, and regulating my wood input accordingly, I see my end point coming two hours before it happens. To a large extent I can make it happen exactly when I want it to.

All of that is critical if you have loaves of bread rising and you want to put them in at a certain time. And since different batches of bread (especially sourdough) rise at different rates (even when using the same recipe) the ability to control/predict when your oven will be at the right temp is HUGE.

But...if all you plan to do is cook pizza, all you need do is get the hot face up to 800 or better... keep it there for an hour or two (depending on how many pizzas you are cooking)...move the coals over...and you are good to go. No need for anything but a IR gun. Just depends what you plan to do.

As far as complexity or holes in the oven...that's a non-issue. For the hearth thermocouples, I simply put two drinking straws in the form for the stand before I poured the concrete. I pulled the straws out as the conrete began to set up. For the thermocouples in the roof vault it was easier. One TC I simply laid in place and set a small piece of brick on it to hold it still before I put the insulation blanket over it. The other one I drilled two inches into a roof brick, pushed the TC into the hole, and layed the blanket over it. Nothing to it.

Your mileage may vary on the usefulness, but complexity of instalation is not an issue.

Bill
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Thermocouple design for oven maburton Tools, Tips and Techniques 24 08-04-2012 10:24 AM


All times are GMT -7. The time now is 02:12 PM.

Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.0
2006/10 Forno Bravo, LLC