Door glass - Is it mandatory?

[HotCoals]

I don't think I have ever heard or seen someone make that statement. It almost boggles my mind and puts me in sheer disbelief.
The science behind it if anyone cares.
Most all metals, specifically steel and cast iron when talking about wood stoves conduct heat anywhere from 150-300x better than glass. However, glass poses almost no resistance to radiant heat so that is why the glass on a wood stove door puts out so much heat-it is essentially radiating 90% or so of the fires temperature.
Glass has a thermal emissivity rating of .8-.98 depending on the glass, most ceramic glass is .92
Steel has a thermal emissivity rating of .54 -.68 depending on the type
Cast Iron has a thermal emissivity rating of .55-.60
Soapstone has a thermal emissivity rating of .45

The higher the emissivity the higher the temperature a material can radiate, but also is inversely proportional to how long that material will radiate heat. Which is why soapstone will radiate heat for hours after the fire goes out, where as steel and cast iron stoves cool off about 20-30% sooner than soapstone. And glass cools off almost" instantly".

So are you saying it would better to have a all glass stove to get the heat into the house faster or a heavy big mass stove such as a soapstone stove?


Were talking theory here with a little thermal dynamics thrown in...lol.

 

[Seasoned Oak]

A wood stove without a viewing window is like a TV with no picture. And a picture is worth a thousand words.

 

[ambull01]

So are you saying it would better to have a all glass stove to get the heat into the house faster or a heavy big mass stove such as a soapstone stove?
Were talking theory here with a little thermal dynamics thrown in...lol.

I've been trying to figure out who he was responding to for a couple days now lol.

 

[HotCoals]

I've been trying to figure out who he was responding to for a couple days now lol.

me too..lol.

 

[ambull01]

me too..lol.

Thanks. I thought I was just having a prolonged blonde moment.

 

[HotCoals]

Thanks. I thought I was just having a prolonged blonde moment.

lol


I think the best way to get the most heat from a given amount of wood is to just put the wood on the floor and light it off.

Of course that would not be good for the house or a human.
So we put the fire in a box and run a flue out the roof to save the house and us from being burnt up..that's a good thing.
In my mind anything that slows the transfer of heat from that box to the room is lost heat up the flue.
I don't think steel,cast,soapstone or anything can bank enough heat to make up the difference of what went up the flue from lack of good transfer.
Maybe I'm thinking all wrong. If I were to ask my wife I'm sure she would say I'm wrong..lol. So I'm throwing it out on here and I may have at least one that may agree with me.lol

EDIT: To clarify,I believe glass would transfer heat out of the box faster then anything else.

 

[ambull01]

lol


I think the best way to get the most heat from a given amount of wood is to just put the wood on the floor and light it off.

Of course that would not be good for the house or a human.
So we put the fire in a box and run a flue out the roof to save the house and us from being burnt up..that's a good thing.
In my mind anything that slows the transfer of heat from that box to the room is lost heat up the flue.
I don't think steel,cast,soapstone or anything can bank enough heat to make up the difference of what went up the flue from lack of good transfer.
Maybe I'm thinking all wrong. If I were to ask my wife I'm sure she would say I'm wrong..lol. So I'm throwing it out on here and I may have at least one that may agree with me.lol

EDIT: To clarify,I believe glass would transfer heat out of the box faster then anything else.

I don't know about that. In essence, wouldn't that be an open fireplace? I'm totally ignorant about wood burning but I do know using my old open fireplace made the house colder. The box must be doing something right, just not sure exactly what.

Perhaps we should stop this discussion. I think we're dumbing down this thread lol. Dumb and Dumber? I can be Dumber, I don't mind.

 

[HotCoals]

I don't know about that. In essence, wouldn't that be an open fireplace? I'm totally ignorant about wood burning but I do know using my old open fireplace made the house colder. The box must be doing something right, just not sure exactly what.

Perhaps we should stop this discussion. I think we're dumbing down this thread lol. Dumb and Dumber? I can be Dumber, I don't mind.

Lol no a open fire with no flue would be the most efficient way to heat up your house for sure..lol.

 

[gerry100]

with the new EPA stoves I think viewing the fire is important to making adjustments and managing the fire

Also better than most of what's on cable

 

[ambull01]

Lol no a open fire with no flue would be the most efficient way to heat up your house for sure..lol.

Oh I see, true. That would be great. Then I could make several fires in all the rooms downstairs without having to worry about not having a chimney. Issue with distributing heat solved. No need to keep reading about secondaries, removing baffle to clean flue, flue liner, etc. Such a relief.

 

[HotCoals]

Oh I see, true. That would be great. Then I could make several fires in all the rooms downstairs without having to worry about not having a chimney. Issue with distributing heat solved. No need to keep reading about secondaries, removing baffle to clean flue, flue liner, etc. Such a relief.

 

[Huntindog1]

If you can wrap your brain around Emissivity......................

Than you will master this subject.

http://en.wikipedia.org/wiki/Emissivity

 

[HotCoals]

If you can wrap your brain around Emissivity......................

Than you will master this subject.

http://en.wikipedia.org/wiki/Emissivity

Too much reading..lol.
I know the heat will pass through glass faster then steel..it has to.

 

[Huntindog1]

Dont try this at home!

 

[ambull01]

If you can wrap your brain around Emissivity......................

Than you will master this subject.

http://en.wikipedia.org/wiki/Emissivity

Okay read it. So as I understand it (which is exactly what TheRambler said), high emissivity levels mean the material is effective at emitting thermal radiation. Glass windows are near the maximum value of 1.0. Low-E windows reduces heat loss because they absorb less heat. I think.

Black is the ideal color for emissivity which is why I sweat my butt off wearing black clothes during the summer. Reading that makes me think black creosote would be especially dangerous not just because of the flammable nature but also the color will absorb more heat.

Am I on the right track or did I just screw that all up?

 

[ambull01]

Wait a minute. Is that why soapstone is chosen to line the insert? It has a lower emissivity rating than steel and you ideally want all of the heat from an insert to exit from the face into the room. If you had steel for the front of the insert it would take longer to heat up thus you would have to wait longer for heat to radiate into the room. If I'm wrong I'll stay out of this site for the rest of the day. Brain hurts.

 

[HotCoals]

Wait a minute. Is that why soapstone is chosen to line the insert? It has a lower emissivity rating than steel and you ideally want all of the heat from an insert to exit from the face into the room. If you had steel for the front of the insert it would take longer to heat up thus you would have to wait longer for heat to radiate into the room. If I'm wrong I'll stay out of this site for the rest of the day. Brain hurts.

What you said sounds reasonable to me...course that and a buck may get you a cup coffee. lol

 

[ambull01]

What you said sounds reasonable to me...course that and a buck may get you a cup coffee. lol

No you know what, still doesn't make sense to me. I can see why you wouldn't want an all glass insert/stove. The heat would just pour out of that sucker and roast you. You want the heat to come out slow, relatively speaking. Buuuuuut, the part that doesn't make sense is this:

"The higher the emissivity the higher the temperature a material can radiate, but also is inversely proportional to how long that material will radiate heat. Which is why soapstone will radiate heat for hours after the fire goes out, where as steel and cast iron stoves cool off about 20-30% sooner than soapstone."

If soapstone has a low emissivity rating, it will take longer for it to heat up and will never be able to get as hot as steel. Even if it does radiate heat much longer than steel, you've just lost a ton of heat trying to get the soapstone hot vs just having steel. The only way it makes sense to my pea brain for having soapstone in your insert is to take advantage of it's low emissivity rating. I would think you want that so most of the heat gets the hell out of the insert to heat your room/house not to radiate heat because it takes so much longer for it to achieve similar temperatures in comparison to steel.

Just blew my own mind.

 

[HotCoals]

No you know what, still doesn't make sense to me. I can see why you wouldn't want an all glass insert/stove. The heat would just pour out of that sucker and roast you. You want the heat to come out slow, relatively speaking. Buuuuuut, the part that doesn't make sense is this:

"The higher the emissivity the higher the temperature a material can radiate, but also is inversely proportional to how long that material will radiate heat. Which is why soapstone will radiate heat for hours after the fire goes out, where as steel and cast iron stoves cool off about 20-30% sooner than soapstone."

If soapstone has a low emissivity rating, it will take longer for it to heat up and will never be able to get as hot as steel. Even if it does radiate heat much longer than steel, you've just lost a ton of heat trying to get the soapstone hot vs just having steel. The only way it makes sense to my pea brain for having soapstone in your insert is to take advantage of it's low emissivity rating. I would think you want that so most of the heat gets the hell out of the insert to heat your room/house not to radiate heat because it takes so much longer for it to achieve similar temperatures in comparison to steel.

Just blew my own mind.

That's not the point right now...see what I'm saying?
Were trying to get the most heat into the room per lb of wood.

 

[ambull01]

That's not the point right now...see what I'm saying?
Were trying to get the most heat into the room per lb of wood.

Oh you're absolutely right. Yeah, a glass stove would do that. So this is exactly like comparing soft vs hard firewood. Soft woods like pine would will burn fast and throw off a lot of heat. Hard wood will burn slower and throw out heat longer. If you want to roast alive, use a all glass stove with fast burning soft firewood.

 

[HotCoals]

Oh you're absolutely right. Yeah, a glass stove would do that. So this is exactly like comparing soft vs hard firewood. Soft woods like pine would will burn fast and throw off a lot of heat. Hard wood will burn slower and throw out heat longer. If you want to roast alive, use a all glass stove with fast burning soft firewood.

Again to me that sounds reasonable..and again that and 3 bucks may get you a beer!

 

[ambull01]

Again to me that sounds reasonable..and again that and 3 bucks may get you a beer!

I need a beer right about now. Need to cool my brain cells off.

 

[HotCoals]

I need a beer right about now. Need to cool my brain cells off.

Well I think you said you're a blond..that should help..maybe better to shave your head?

 

[bholler]

Hot coals your theory makes sense but its not completely correct the heat used to heat us the thermal mass of a soapstone stove masonry heater or even a cast stove is not lost heat it is stored heat that will be released later it makes for a much more even heat without the big spikes in heat with other stoves. Yes it takes much longer to get heat out of the stove so if you are trying to heat a place up quick like a shop or a cabin a thinner steel stove or a glass stove which would be cool as hell would be better.

 

[HotCoals]

Hot coals your theory makes sense but its not completely correct the heat used to heat us the thermal mass of a soapstone stove masonry heater or even a cast stove is not lost heat it is stored heat that will be released later it makes for a much more even heat without the big spikes in heat with other stoves. Yes it takes much longer to get heat out of the stove so if you are trying to heat a place up quick like a shop or a cabin a thinner steel stove or a glass stove which would be cool as hell would be better.

my answer to that is that at least with steel,cast and soapstone the mass can't beging to hold the amount of heat that went up the flue.

Now a high mass masonry made to do the job with a short very hot fire maybe diff imo.