Dirty glass - definition and cause question

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Andy S.

Feeling the Heat
Oct 28, 2013
405
Southeastern, PA
I didn't want to hijack a couple of threads I've been following that mention dirty glass but were started on other subjects. My "dirty glass" from last year needed to be scrubbed from the glass. I attributed it to the wood and my learning curve.

This year's "dirty glass" is more of a light haze or dust and comes off with nothing more than a light swipe from a damp paper towel. I'd been thinking this is normal but reading the other threads I'm not so sure.

Does anyone keep crystal clear glass? If so, are there any operating suggestions to get there?
 
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The drier the wood and the hotter the stove will provide the cleanest glass. Some stoves just aren't as good as keeping the glass clean. Don't be a slave to your glass. As long as your wood is seasoned and your temps are good, don't worry so much.
 
This year's "dirty glass" is more of a light haze or dust and comes off with nothing more than a light swipe from a damp paper towel.

Very common - it is nothing more than ash. When you turn hundreds of pounds of wood into ash some of it is gonna move around. And yes, some is gonna deposit on the glass. I don't know of ANY glass front stove that doesn't need a wipe off once in awhile.
 
I read the thread about the Appalachian 52 Bay. The OP didnt elaborate if he had resolved the blacking in the bay windows on his insert.
Love this insert, found a Quadrafire that had a bay window set up on an insert. The glass may be a selling factor but a massive disappointment if the glass turns black no matter what you do. I'd rather have a great view of the fire and freeze in my house than have airtightness and btus in my stove.
I have a VC and the glass stays clear if the wood is correctly seasoned. Im assuming this stove design has resolved any air wash features. Any resins or residue I attribute to moisture in the wood. And maybe not enough air.
I try to stretch the burn time and I think it compromises burn quality. (For overnight burns)
Its all good though, I love that 52Bay. I want one. I just NEED clean glass too.
I think its both manufacturing design and burning habits combined.
 
I think draft has a lot to do with dirty glass. With wood that isn't completely seasoned, I get a dark glaze in the beginning half of the burn cycle and sometimes a gray coating at the end. With extremely dry slab oak, I only get the gray stuff at the end of the cycle, unless I'm giving it a lot of air. I wouldn't the consider the draft from my 15ft flue to be weak or strong, slightly less than moderate I guess. I think the gray stuff is just lingering ash residue that doesn't have a strong enough draft to pull it out at that point in the cycle. Luckily, I don't get much of the dark stuff.

Anyway, it's fairly easy for me to keep clean. The dark stuff is a little more difficult to remove, but not that bad really. Every morning, before I load the stove, I go over the inside of the glass with #0000 steel wool until it's clear. It usually takes no more than 30 seconds. After about a week of cleaning it this way, it gets a film on it and becomes more difficult to keep clean. That's when I leave the door open for a few minutes to let it cool down and then clean it with windex sprayed on a wet paper towel which gets rid of the residue.
 
The airwash on the 30 work outstanding with dry wood and a hot fire going but there still is a little gunk - sometimes more/sometimes less - after an overnight. Damp paper towel typically wipes it right off if you get it at around 1-200 degrees. Or just leave it and let the airwash do the dirty work with the next load.

If I let the stove cool off the glass crud takes more effort to remove. Get it while its hot
 
The glass on my old stove got really dirty and was difficult to clean. The glass on my new stove stays crystal clear unless the end of a log gets too close to it. Maybe as the stove and glass age they get dirtier?
 
Anyway, it's fairly easy for me to keep clean. The dark stuff is a little more difficult to remove, but not that bad really. Every morning, before I load the stove, I go over the inside of the glass with #0000 steel wool until it's clear. It usually takes no more than 30 seconds. After about a week of cleaning it this way, it gets a film on it and becomes more difficult to keep clean. That's when I leave the door open for a few minutes to let it cool down and then clean it with windex sprayed on a wet paper towel which gets rid of the residue.
I know it's not actually "Glass" and it is tough stuff, but I would be afraid to use any abrasive substance to clean it. ( I know some here use the ashes).

I would think even 0000 wool would make tiny/micro scratches that MAY attract even more dust/ash. Not sure though.:confused:
 
I have not had anything on my glass that would not wipe off with a damp towel since the first season. I do get a light film of ash that is clearly deposited by the airflow pattern set up by the secondary tubes. I suspect that the movement of the ash across the face of the glass creates a bit of static charge that holds it there.
 
I know it's not actually "Glass" and it is tough stuff, but I would be afraid to use any abrasive substance to clean it. ( I know some here use the ashes).

I would think even 0000 wool would make tiny/micro scratches that MAY attract even more dust/ash. Not sure though.:confused:
So you are subtly telling me that what I'm doing is wrong, even though you don't know yourself. If not, what is the point of your post?
 
Does anyone keep crystal clear glass? If so, are there any operating suggestions to get there?

I have had good luck with closing my primary air just about tight with a modification (magnet covering all but a sliver of the inlet when fully closed). I have a rear air control on my stove which I open a quarter and it helps air mix with the smoke at the back of the box so it burns up before it gets to the glass. I get alot better secondaries and more heat from them as well. And still getting 9 hr burns to boot. I think this happens because its more like a top down fire rather than a n/s fire. I still get a little haze on the glass that needs to be cleaned off about every week and a half.
 
Great replies, thanks. My takeaway is that anything able to come off with a light wipe with a damp paper towel is normal and not a sign of wet wood or bad practice. Anything that needs to be scrubbed is a sign of a problem.
 
My first year I was getting my glass nice and brown daily. I couldn't understand why. After I found this site I get a bit of brown in the bottom corners but most of the time I am able to burn it right off. I wouldn't call it a problem. It's just the way stove is designed to send the air. Those are the coldest corners and that's why (moisture soot) deposits when I reload the stove. At least that's how I see it.
 
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So you are subtly telling me that what I'm doing is wrong, even though you don't know yourself. If not, what is the point of your post?
Pretty sure I didn't say you were wrong. I said "I would be afraid to use any abrasive substance".


See it's called an internet forum. See, it's where people come to toss ideas around in hopes of gaining feed back and additional knowledge from others on a similar topic.

So, when I post a thought (even if I am not 100% certain of my idea as "the gospel") then it means I am looking to expand my knowledge from others here and gather their opinion also. Was hoping to see if others thought 0000 wool may be too harsh.
THAT was the point of my post.:rolleyes:
 
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Pretty sure I didn't say you were wrong. I said "I would be afraid to use any abrasive substance".


See it's called an internet forum. See, it's where people come to toss ideas around in hopes of gaining feed back and addietional knowledge from others on a similar topic.

So, when I post a thought (even if I am not 100% certain of my idea as "the gospel") then it means I am looking to expand my knowledge from others here and gather their opinion also. Was hoping to see if others thought 0000 wool may be too harsh.
THAT was the point of my post.:rolleyes:
Then expand the knowledge of others by telling them something you know instead of something you're "not sure" of.
 
Then expand the knowledge of others by telling them something you know instead of something you're "not sure" of.
OK bub.:rolleyes:
 
My Summit and T6 developed a very stubborn thin coat of white opaque film on the glass over the years and I cannot remove it at all. I tried all the methods mentioned without success.
Any help will be appreciate
 
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Easy guys....
 
Then expand the knowledge of others by telling them something you know instead of something you're "not sure" of.

Enough already.
 
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