How hot for clean glass

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jkupcha

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Dec 21, 2006
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For those lucky enough to get their stove hot enough to keep their glass clean, can you tell me what temp is required to burn off any residue? I get my Napoleon NZ6000 pretty darn hot but obviously not hot enough to keep creosote from forming on the glass. Is there a figure out there to shoot for? could a magnetic temp gouge on the glass give a good figure? THanks.
 
Make sure you're wood's dry, keep the wood (especially the ends of the splits) away from the window, don't shut it down to a low smoldering fire, remove ashes regularly, and keep the ashes from piling up where the combustion air enters the firebox. No matter what you do, I think the odds that you'll ever get a "magnetic temp gouge" to adhere to a piece of glass (or actually transparent ceramic) are essentially nil. You need a thermometer, and if it's a magnetic type, you need to attach it to something that's ferromagnetic...stove front, stovetop, stovepipe. Rick
 
ferromagnetic

From you, that word could be a double edged sword. "Ferr" as in ferret, etc .

I picture a ferret stuck to my fridge
jawdrop.gif
.

:lol:
 
I've never (yet) been successful in getting a magnet to stick to a Ferret. I think that out here in Oregon, all our Ferrets must suffer from some sort of iron deficiency. I'll try changing their diet, because I can think of some advantages to them being magnetic, in terms of ease of handling & processing. Rick
 
Stick with the low iron ferrets Rick. The high iron ones get freaked out when riding in the maglev.
 
I like listening to them squeak. %-P Rick
 
Hot is good but i have found that most of the glass contamination comes from starting fires with the fuel close to the glass. Try a cold start with the wood in the back half of the box. The other issue is when you add to a hot box try to keep the ends away from the front. Since doing this I have no problems with dirty glass.
 
My glass stays clear all day because we adjust the air as needed.
1 hour before bed I load it full with small splits in the front and large in the back, all E/W.
I try to keep everything as far back as possible.
I get it cranking and slowly turn down the air until it's almost closed. It seems to cruise there +/- 500 deg.
In the morning I'm down to just a few coals and the glass is smoked. I wipe (sometimes scour) it off before stoking it back up because I haven't been able to burn it off with a new hot fire.
I guess there's just not enough air wash or temp. to keep it clean when the fire gets near the end of the burn. I'm afraid if I leave it with much more air it would overfire at some point during the night.
I wish I knew a way to prevent the smoked glass but I don't think there is, at least for this setup. My gaskets seem ok except one very small spot on the griddle top. I'll look for some rope for that today.
Any advice appreciated.
 
fossil said:
I've never (yet) been successful in getting a magnet to stick to a Ferret. I think that out here in Oregon, all our Ferrets must suffer from some sort of iron deficiency. I'll try changing their diet, because I can think of some advantages to them being magnetic, in terms of ease of handling & processing. Rick

Rick, thats easy, use a stapler!!! %-P
 
banger said:
For those lucky enough to get their stove hot enough to keep their glass clean, can you tell me what temp is required to burn off any residue? I get my Napoleon NZ6000 pretty darn hot but obviously not hot enough to keep creosote from forming on the glass. Is there a figure out there to shoot for? could a magnetic temp gouge on the glass give a good figure? THanks.

If you are getting creosote on the glass, there is only one answer. Your wood is not seasoned! You need some dry seasoned wood, pronto.
 
All of the above addressed the basic concerns (well, with the exception of Ricks magnetic ferrets). But to address your question specifically. If you are in the "safe" range of burning temps. especially if on the upper end of them (say 600F or above for discussions sake), you should have no problems with the glass gunking up. That is the numbers you were looking for.

Now, if you still have the glass gunking up, review the above suggestions. They were good ones (including the ferrets :lol: )
 
Even with 18% internal moisture content I can gunk up my glass, by dampering down to low overnight. Trying to get those long burns there can be a trade off.
 
Smokey said:
Even with 18% internal moisture content I can gunk up my glass, by dampering down to low overnight. Trying to get those long burns there can be a trade off.

Yep, it sure can, but chances are - you are dipping below the "safe zone" temps.
 
It could be the wood banger...unseasoned wood is real difficult to keep glass clean. Now that we can see the fire I'm real careful to keep the glass clean.

Monday was a cold morning with a warm afternoon the XO left for work and shut down the air a little too much so by the time I got in the glass was the blackest its ever been...you couldn't even see the flames. So I threw some smaller splits in and open the primary air. After a good burn of about 650 for a couple of hours it cleaned up enough so it was acceptable. Not perfect the way I like it but I was amazed it even cleaned up at all...the glass was as dark as a welders mask. Still haven't touched the glass and it's pretty much really clean as of right now. Of course it's colder with snow so were burning more regular at 500-550.
 
I could be Jags, I just don't want the fire to burn out before I get up in the morning. Or on the other side of the coin have to put the ceiling fan on in the bedroom and open a window like I did a week ago.
 
For the little Avalon I used to run, I found there was a temperature range where not only did the glass not load up with stuff, but stuff that was already on it would burn off just like a self-cleaning oven. Pretty miraculous watching the glass actually get clearer during the course of a burn.

Roughly speaking that "range" was between half and full output based on what the stove was capable of putting out in terms of heat (or in terms of burn rate). Or in other words, pretty hot... I have to say that I mostly got to enjoy this miraculously clean glass during January and February, and the rest of the time I had smudges and hazes on the glass to varying degrees.

"Half to full output" corresponded to flue gas temperature in the 600-750F degree range, as measured inside the flue collar with an industrial bimetal probe-type thermometer. I remember checking the glass temperature with an IR thermometer at some point and finding it to be *really* hot, several hundered degrees at least... but I forget the exact reading.

OTOH the old Jotul 8 I'm now trying to burn doesn't even have an airwash... I haven't yet found the temp at which it will keep its glass clean, and I'm not sure there's going to be one.

Eddy
 
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