Insulating the vent area

[PlanoPhil]

I've noticed that some people insulate the vent area and so do not. I'm installing a Casa90 and was wondering if this is overkill. I live in North Texas where 20 degrees is about the bottom and that happens rarely and besides who wants to stand outside and cook in freezing weather?

Thanks
Phil

[GianniFocaccia]

Re: Insulating the vent area

I don't think the insulation is to keep the vent and flue warm in cold weather. It's to minimize the amount of heat loss once your pizza session has concluded and you want to rely the retained heat to cook something else later.

[Les]

Re: Insulating the vent area

I insulated there, only because I transitioned to non-refractory materials.

[azpizzanut]

Re: Insulating the vent area

Hi PlanoPhil,

The vent is not tied to the dome so there is no reason to insulate it. Ask, why would it need to be kept warm? You don't cook in it and, it contributes nothing to a pizza or roast. If I had given it some thought in advance, I would have placed a little insulation on the front of the vent where it nearly contacts the cement board facing of the enclosure.

Cheers,

[GianniFocaccia]

Re: Insulating the vent area

The vent is not tied to the dome so there is no reason to insulate it. Ask, why would it need to be kept warm? You don't cook in it and, it contributes nothing to a pizza or roast.

Good point, Bob. However, in my case, I have concluded there will be a benefit to insulating my entire entryway and vent. Here's my thinking (which could be dangerous!)

My entryway, floor and vent will be completely separated from the dome by a heatbreak. The only contact it will have with the dome will be a 1/2" of firebrick touching the face of the inner arch of the dome (ala TScarborough). This minimal contact area is to reduce the amount of heat leakage from the dome once the pizza party is over and the oven gets closed up for the night.

We know that one of the properties of heat transfer is the temperature differential of the two elements transferring heat. My logic is: the hotter I can keep the entryway (from escaping hot flue gases during pizza making) the lower the differential and the less heat gets transferred. Hence, the need for entryway and vent insulation.

Sound logical?

[PlanoPhil]

Re: Insulating the vent area

This is an interesting discussion however I don't know if it is germane to my situation. As I stated, I am installing a Casa 90 which is one solid dome/entry way, albeit in three pieces. There is no separation between the dome and the entry/vent. That said is it advisable/necessary to insulated the vent area? I'm thinking yes but I'm still a serf.

Phil

[azpizzanut]

Re: Insulating the vent area

Hi Planophil,

You're right, sorry about that.

Cheers,

[lwood]

Re: Insulating the vent area

No Pizzanut you are correct, there is always a separation btw the dome and the vent. It's called the door. Once the door is closed, the vent cools enough to put your hand on it in a few minutes. Mine is SS. With the door open it can be almost glowing hot. That said, insulation around the vent is meaningless with the door closed. Personally, I believe it's only purpose is structural to hold the vent in-place. The insulation can get pretty thin in front of the vent over the arch. It also keeps you from touching a hot stainless steel pipe if you put it high enough. But adding to the retained heating value, I doubt it.....just put you hand on the pipe after put the door on.

[james]

Re: Insulating the vent area

Hi guys,

With the FB modular ovens, the vent and vent walls are cast refractory and they are integral with the oven opening. It's a nice feature that makes assembly easy, it's very durable, it gets hot quickly so it draws well, and there aren't any seams at the oven opening. It's a good thing. :-)

The oven kit comes with enough insulation to easily cover the vent area, so there really isn't any reason to not cover it. Plus, the vent area does eventually get hot when you are firing your oven. Not as hot as the oven chamber, but still hot.

This graphic shows how the vent area works.

Go for it.

James

[ptone]

Re: Insulating the vent area

I just put in my casa 80 and used 1" of insulation in the vent area and three for the oven. I actually have 2" across where the dome transitions to the vent that results in a better taper from dome to vent.

outdoor kitchen - a set on Flickr

-P

[rossano]

Re: Insulating the vent area

I just put in my casa 80 and used 1" of insulation in the vent area and three for the oven. I actually have 2" across where the dome transitions to the vent that results in a better taper from dome to vent.

outdoor kitchen - a set on Flickr

-P

And 1" is enough over the vent area as to not allow high temps on the outer layer? Ie: stucco?

[BriggsARNP]

Re: Insulating the vent area

Does it matter which kind of chimney you use? Dura tech vs. a single walled type of chimney. I would imagine that the duratech chimney isn't very hot on the outside where a single walled chimney might be a lot hotter.

[ptone]

Re: Insulating the vent area

And 1" is enough over the vent area as to not allow high temps on the outer layer? Ie: stucco?

If you look on page 9 of the install, it doesn't show any insulation. I called FB and they said 1" should suffice, I would maybe to 2-3 along the very top where the vent meets the dome, as that is where the flames lick and hot gases go.

But there are two purposes to insulation, one is heat retention (which really only matters for the dome/cooking area. And the other is safety/touch, which for the right around the metal chimney is of limited value anyway because the chimney gets stinking hot anyway...

-P