#1  
Old 05-21-2007, 12:57 AM
threestring's Avatar
Serf
 
Join Date: May 2007
Location: Iwate, Japan
Posts: 1
Question Vent/Opening and Heat Conductivity

I'm thinking about how to build the vent and opening for my oven, and most of the pictures I've seen so far show the corridor leading into the opening to be constructed out of fire brick. Wouldn't using a conductive material like fire brick or terracotta pull heat out of your oven? Wouldn't clay brick or something more insular help hold in the heat?

So, has anyone had problems with heat bleeding out the opening structure? And has anyone done anything creative to prevent this? Or is it not that big of a problem? Any advice is much appreciated!

Ethan
Reply With Quote
  #2  
Old 05-21-2007, 04:42 AM
james's Avatar
Brick Oven Merchant
 
Join Date: Mar 2005
Location: Pebble Beach, CA
Posts: 4,648
Default Re: Vent/Opening and Heat Conductivity

Welcome Ethan,

How did you come to be in Japan? It will be fun to see photos of your oven going up in the context of a Japanese neighborhood.

Good question on the vent material. Both firebrick and clay bricks are thermal, in that they absorb and hold heat -- as opposed to insulators such as Infulfrax, SuperIsol, vermiculite, perlite, insulating firebricks, etc. which are pumped full of air holes and block heat. It is OK building your vent and vent walls from either firebrick or clay brick, as it doesn't get too hot in the vent area and it does not see direct exposure to flame.

There isn't a problem with the vent being made from a thermal or refractroy material, as it is good for the vent to get hot and draw hot air from the oven, and promote convection. It is far enough away from the serious heat so that it does not wick heat from the oven.

In fact, the vent walls and vent pieces for othe Casa oven are all made from the same material as the rest of the oven. The vent walls are built into the pre-cast dome pieces.

Hope this helps -- I am looking forward to seeing some local photos.
James
__________________

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Reply With Quote
  #3  
Old 05-21-2007, 10:57 PM
Journeyman
 
Join Date: Oct 2006
Location: Adelaide, Australia
Posts: 257
Default Re: Vent/Opening and Heat Conductivity

James,

What you say makes perfect sense for direct pizza cooking. I plan to have firebrick out to and including the oven door opening, then make a transition to red clay brick on the sides and front of the vent chamber, as well as above the oven for the chimney. The MTA oven (see pic) shows how I plan to do it, except that the sides of my vent chamber will be straight rather than angled, and be of clay brick.

I have to have clay brick anyway on the sides of the vent chamber, as these will be situated in the middle of my bench top, and only one brick thickness thick. So done for appearance more than practicality.

I’m also wondering if it would be a good idea, in the transition from firebrick to clay brick, to have a small gap (having regard to structural considerations) and stuff the gap with insulation blanket. Above the vent chamber, I was thinking of isolating the flue/chimney (which may simply be a single leaf of clay brick) with either some insulating firebricks, or like Drake, with some sort of cast insulating refractory material.

The only reason I'm considering going to this trouble is for bread baking – I thought with these insulating ‘barriers’ there might be less heat drain from the oven after the fire is removed.

Comments?

Paul.
Attached Thumbnails
Vent/Opening and Heat Conductivity-oven46.jpg  
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
pompeii oven construction began today paulages Pompeii Oven Construction 207 06-18-2014 03:19 AM
High Heat Mortar Primer james Getting Started 80 01-27-2014 06:40 PM
Appropriate Heat stevenki Heat Management 19 10-16-2011 09:47 AM
High Heat Wood Fired Roast Turkey aikitarik Roasting and Grilling 21 12-24-2010 09:32 PM
Holding High Heat james Newbie Forum 10 12-22-2010 07:05 PM


All times are GMT -7. The time now is 02:52 PM.

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