Door glass - Is it mandatory?

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Distruct

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Nov 12, 2014
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US
Hey all, first post so be gentle...

I am in the research stage of installing a wood insert into a large fireplace. I have been looking at a lot of manufactures offerings and one thing stands out....every single insert has glass doors! why is this, is it mandated? I have no desire to see into a fire, it is just for heat and I cannot imagine that glass would radiate better than metal let alone last as long. Of course they would need to be cleaned as well, not looking forward to that. I do understand that Cat stoves need a window so the door is not opened while at temp but what about non-cat stoves?

Thanks for any insight into this, i searched for some time but could not find anything of note.
 
You get a lot of heat radiated through the "glass" (actually a ceramic) door . . . but I think the primary reason for having the ceramic doors is not for the heat, but rather for the ability to watch the fire . . . it's almost a primeval thing . . . most people just like to watch the fire whether it be a camp fire, fireplace or even in a woodstove or woodstove insert. I cannot tell you how many times in the evening when I have turned off the TV and just sat in my chair watching the flames before finally going to bed. I suspect you would find that inserts without the ceramic window to the fire would not be very big sellers . . . in fact, if memory serves me correctly, Woodstock used to make a soapstone stove that had no ceramic . . . but since introducing other stoves it seems as though they do not make this model any more -- perhaps because it was not a big seller.

There is an added benefit to being able to see the fire though . . . you can see at a glance where the fire is in terms of what stage it is at and know whether you should reload or not.

Most modern stoves also have decent air wash systems which means that as long as a split doesn't rest up against the ceramic, the wood is truly seasoned and you're burning at the right temp you shouldn't have it gunk up. In my own case, after a week or so I do get some fly ash and discoloring on the glass, but a swipe with damp newspaper or paper towel fixes this issue.
 
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I have no desire to see into a fire, it is just for heat
I believe you would be in the minority. If you ever saw a good wood stove in action you may change your mind. My harman reminds me of the northern lights in the arctic and puts on quite a show. Its better than fireworks and just as colorful. I consider it in the top three reasons to own and operate a wood stove.
 
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I literally felt the glass last night out of curiosity. Stove was burning at 300 and I wanted to see how hot the glass was. Big mistake. It was way hotter than the stove-top, that's for sure. i will never do that again!
 
You get a lot of heat radiated through the "glass" (actually a ceramic) door

My has wife scorched flannel pajama pants standing in front of the stove in the morning. I'm pretty sure that wouldn't happen with a steel door.

Blaze King offers (they used to, anyway) a steel door instead of glass. Not sure about the Princess insert, but it was available for the freestanding stoves.
 
Yeah im going to echo what everyone else has said, the glass/ceramic radiates a TON of heat, way more then sides or top of the stove. It just may not hold the heat as long as the cast iron or soapstone does.

Also im really confused as to why you would NOT want to see the fire? not only is it nice to watch but its very helpful for managing the fire, sure a thermometer is useful but being able to see if the stove is going nuclear when starting a fire and the stovetop thermometer only says 200-300 will give you a good indication that you may want to shut the door/shut down the air supply.

plus as other said, new stoves have good air washes and when burning properly seasoned wood the glass does not get that dirty. I only wipe it down with a damp paper towel when I empty the ashes. takes me 5 seconds.
 
I have a steel door on my old VC. Back then, glass was an $$ option.

Gotta admit, watching the fire would be better than most TV shows these days.::P
 
I would love to see how a all glass stove would perform. Forget storing heat in steel or cast..heat transfer to the room is what you want! lol
 
Not mandatory, but:

1) Ambiance - you can see the fire and have some firelight in the room
2) Heat - glass does allow more heat to radiate through, though some new stoves actually have an aluminized coating on the glass to keep heat in the firebox for more complete combustion. You likely get that 'reflected' heat back from the walls of the stove...plus a bit more if it helps combust even more smoke.
3) Fire tending - this could be a big one depending on how closely you watch the stove. On countless occasions, I've made small adjustments to keep the secondaries lit, or get them to light because I can see what's going on inside the firebox. With a steel door, I'd just be getting 'some heat' so who knows how efficiently things are burning. If you open the door to take a peek, then you change the air cycle which was in place with the door closed, so you never really know how things were burning.
 
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If ya like glass theirs one of these listed on Craigslist in metro Detroit for a $1000.00 (broken link removed) Pretty crazy !!! click on the photo's they enlarge. Jay
That thing is crazy..would love to run it for a few days!
I would get rid of the grate and put some sand in the bottom though. Tough for just getting some fast heat for cooking the grate prolly would work better.
 
This forum rocks, you all are awesome!


So you are the one......;lol
haha, appears so!

In reality it might be because that is what my experience is with. I've been burning for years but always in an older insert; timberline, kraft, can't remeber the two others. This will be the first new one going into an old farmhouse we renovated. New chimney with 12" liner but didn't have the $$ for a stove at that time.

Thanks for the info all. Now onto figuring out whats gonna make the wallet & wife happy.....er...
 
I think the glass is important to learning these new EPA stoves with secondary flames. Now alot of times in a CAT stove you cant see much of the cat maybe a glow you can go by the temp jumping up.

If your worried about a log rolling out on the glass just get you a stove that can be loaded North/South. North/South Loading is where you put the splits into the stove and you can see the ends of the splits thru the glass. East/West Load is loading the splits side to side. Ends of the splits are to the sides of the stove.
 
This will be the first new one

Be aware - EPA stoves like dry wood. Those old stoves could grind through fuel that simply won't burn (well) in an EPA stove.
 
You get a lot of heat radiated through the "glass" (actually a ceramic) door . . . but I think the primary reason for having the ceramic doors is not for the heat, but rather for the ability to watch the fire . . . it's almost a primeval thing . . . most people just like to watch the fire whether it be a camp fire, fireplace or even in a woodstove or woodstove insert. I cannot tell you how many times in the evening when I have turned off the TV and just sat in my chair watching the flames before finally going to bed. I suspect you would find that inserts without the ceramic window to the fire would not be very big sellers . . . in fact, if memory serves me correctly, Woodstock used to make a soapstone stove that had no ceramic . . . but since introducing other stoves it seems as though they do not make this model any more -- perhaps because it was not a big seller.

There is an added benefit to being able to see the fire though . . . you can see at a glance where the fire is in terms of what stage it is at and know whether you should reload or not.

Most modern stoves also have decent air wash systems which means that as long as a split doesn't rest up against the ceramic, the wood is truly seasoned and you're burning at the right temp you shouldn't have it gunk up. In my own case, after a week or so I do get some fly ash and discoloring on the glass, but a swipe with damp newspaper or paper towel fixes this issue.

This whole post is spot on. I would be totally freaking lost without the ceramic door. I'm totally new to burning wood and feel like I really need to see how the fire is going and monitor the secondary combustion. I still think I'm not doing it right because the ceramic was building up a little soot around the bottom area. Probably not cold enough outside.

My in-laws have a catalytic free standing stove. They've been burning for years but had no idea what secondaries were until I told them the other day.
 
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".
 
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".
You must be a politician :)
 
in fact, if memory serves me correctly, Woodstock used to make a soapstone stove that had no ceramic . . . but since introducing other stoves it seems as though they do not make this model any more -- perhaps because it was not a big seller.

The Woodstock Classic. It looks exactly like the Fireview, just with a solid soapstone face. It was/is (don't know if they still sell it) a cat stove without a window, so there must not have been a requirement for windows in cat stoves.

(broken link removed to http://www.woodstove.com/classic)
 
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I'd have to agree with most folks saying they like to look in through the glass and see how things are burning and judge your air controls by how the fire is burning. Just an example, I have a quad 4300 millinium and a quad 4300 step top. Essentially the same stove, same size, same door, ect. Believe it or not they burn differently. They've made changes over the years and if I couldn't see what was going on, I couldn't run them to the best capacity. Plus most people like me just "zone out" and watch the flames. It's kinda like meditation
 
Get a cat insert. The glass will be black in no time running it low and slow.
<ducking quickly>
 
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I didn't think I'd like the glass in the door but I love it. If you're fire is burning correctly it will stay clean. Very hard to video in the dark ;-)

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