Insulating a new oven

[docsev]

Hi everyone!

First, I am JUST losing my virginity to WFO's. I am in the final installation stages of a 36" insert oven and have begun curing it while I am awaiting the finish of the decorative encasement. (I'm awaiting fabrication of a stone cap to go on a brick box).

This has given me the opportunity to check out some of the heat characteristics of the oven. First, a little about the construction. It is a ceramic shell sitting atop firebrick atop insulating concrete -- I think the base is plenty insulated. The dome has at least 2 inches of insulating castable on it. During my 4'th and 5'th burns to cure, I got the interior dome up to about 500 degrees with the outer dome reaching temperatures of about 150 degrees. After extinguishing the fire, I lost about 150 degrees on the interior dome over the first hour.

I have been reading some of the other threads about heat management and I think what I will do is fill the entire encasement with granular vermiculite. I am wondering if I should, first, put another 2 inches of insulating castable on before the vermiculite and the stone cap? Any thoughts/suggestions?

Also, if I add another layer of castable, do I have to begin the curing process all over again?

Thanks...LOVE the forum!

Dave.

[DrakeRemoray]

Welcome!
It is probably easier to add some insulating blanket then loose fill vermiculite...
Drake

[dmun]

It's hard to make generalizations about insulating castable refractory, because there are so many different products by various vendors for multiple applications. If your enclosure is pretty tight, there is nothing wrong with loose fill vermiculite, the only thing is that it tends to leak out of surprisingly small joints. The blanket is more efficient, but also more expensive

I do know that the outside of your insulated dome should be lower than 150 degrees. Mine's behind a masonry wall, but it hardly gets warm to the touch.

[docsev]

Thanks for the responses! So, another couple inches of castable then insulating blanket, then vermiculite???

[Dutchoven]

Originally Posted by docsev

Thanks for the responses! So, another couple inches of castable then insulating blanket, then vermiculite???

i don't think you need to add any more castable...I would just suggest using ceramic blanket insulation...then you can always pour in loose vermiculite when you get the finish done
Dutch