Soot on Harman XXV glass

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jim2074

Member
Feb 21, 2014
87
Eagle River,WI
I saw some old posts about the glass getting soot on it after a few hours of burning. I have a new Harman xxv and it has happened every day. I am wondering if any found a fix or is it something we just live with.
It looks like an inverted L. Starts in the lower right hand corner and goes up and across the top to the left.
 
Start with your door gasket. Second do you keep a high flame or set to room mode and the fire goes on and off?
 
Mine has done it since new. My father's has too. I used to turn the stove off, and clean the glass with cleaner every day. I no longer do that. I clean it fully once a week, and wipe it with a dry cloth daily. Obviously doesn't get it as clean, but I have learned to live with it. It does suck that the stove is so gorgeous, but the huge glass gets dirty so easily. But at $1K of savings in the first year, it doesn't bother me so much.
 
Ive learned to live with it ! Usually when I clean out the ash every morning i use a paper towel and clean as best i can then on my weekly cleaning I do a better job ! Most important it heats my home for a fraction of the cost of nasty oil
 
Learn to live with it. Most of the XXVs act this way including mine. I clean the glass twice a day with a dry paper towel. Keeps it fairly good until the weekly cleaning when I do a thorough job.
 
Start with your door gasket. Second do you keep a high flame or set to room mode and the fire goes on and off?
Checked door gasket with dollar bill seems good and tight. I burn in Room mode auto. Fan on high, temp at 72, feed rate 4, burning uncle jed's.
 
Higher quality pellets will keep the glass cleaner a bit longer. Not much else you can do about it that I am aware of. I have heard it mentioned the XXV burn pot is closer to the glass then other harman models attributing to a faster build up but I have not personally verified that. Since new my XXV has the same formation pattern. A white haze starts in the lower right corner and arcs acroos the top eventually touching the lower left corner darkening further over time. Unless entertaining I usually clean the glass on the weekly cleanup but the glass is never completely sooted up that you can't see the flame. It bothered me at at first but now I don't give it second thought.
 
It looks like an inverted L. Starts in the lower right hand corner and goes up and across the top to the left.

my xxv is only a few weeks old and has the same EXACT inverted L starting in lower right corner (looks like a lazy7 with a longgg top leaning over to the left). Where they spliced the door gasket is in the same vicinity at the lower right so this is possibly the cause. It's not dark enough to block any fire viewage but it's there nonetheless. Either it's a little better now than when it was brand new or I'm just getting used to it. I've been a bit concerned thinking I may have a leak but it seems as though it is commonplace for this model judging by all the replies here.



Maybe they should have named it the XXV-7 :)
 
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Higher quality pellets will keep the glass cleaner a bit longer. Not much else you can do about it that I am aware of. I have heard it mentioned the XXV burn pot is closer to the glass then other harman models attributing to a faster build up but I have not personally verified that. Since new my XXV has the same formation pattern. A white haze starts in the lower right corner and arcs acroos the top eventually touching the lower left corner darkening further over time. Unless entertaining I usually clean the glass on the weekly cleanup but the glass is never completely sooted up that you can't see the flame. It bothered me at at first but now I don't give it second thought.
Thanks If I get time I will post a picture. By the way your posts and pictures on cleaning your unit were
Higher quality pellets will keep the glass cleaner a bit longer. Not much else you can do about it that I am aware of. I have heard it mentioned the XXV burn pot is closer to the glass then other harman models attributing to a faster build up but I have not personally verified that. Since new my XXV has the same formation pattern. A white haze starts in the lower right corner and arcs acroos the top eventually touching the lower left corner darkening further over time. Unless entertaining I usually clean the glass on the weekly cleanup but the glass is never completely sooted up that you can't see the flame. It bothered me at at first but now I don't give it second thought.
Thanks. When I get a chance I will post a picture. By the way your posts on cleaning the unit with the pictures was outstanding and very helpful. Thanks for doing that.
 
my xxv is only a few weeks old and has the same EXACT inverted L starting in lower right corner (looks like a lazy7 with a longgg top leaning over to the left). Where they spliced the door gasket is in the same vicinity at the lower right so this is possibly the cause. It's not dark enough to block any fire viewage but it's there nonetheless. Either it's a little better now than when it was brand new or I'm just getting used to it. I've been a bit concerned thinking I may have a leak but it seems as though it is commonplace for this model judging by all the replies here.



Maybe they should have named it the XXV-7 :)
Agree. I will post a picture when I get the chance. We love the unit and are very pleased with it's performance. We have only had ours for a week so hopefully it will improve. With what I think we will save on propane I am sure I can live with it.
 
Agree. I will post a picture when I get the chance. We love the unit and are very pleased with it's performance. We have only had ours for a week so hopefully it will improve. With what I think we will save on propane I am sure I can live with it.
Here is a picture of the glass after one day of cleaning. Seems a lot of folks are having this problem. Wonder if Harman would address the issue or comment.
 

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I have owned several different brands of pellet stoves, and not a one would keep the glass clean very long.

A clean glass is dependent on the air wash system in the door or however the stove directs clean air over the glass.

The Quadrafire 1000 uses fresh air from the combustion air plenum that's directed up past the glass.

Our Whitfields draw air past the top of the glass and down over it.

We had a couple Earth Stoves in years past, and they had their own issues.

If you burn a wood product, or any biomass, you get a certain amount of residue from the combustion.

Live with it, as there is no fixing the issue, at least not totally.

We burn nut shells, and the stuff leaves about 2-3 times the fly ash of pellets, plus this same stuff tends to skunk up the glass as well.

We clean the stoves weekly or bi weekly depending on the weather, and the glass gets cleaned with fantastic spray and a little help from an SOS pad to get the stains off.

Having a lovely crystal clear window is not in the offing, at least not for an extended period of time.

The top half of the window will stay clean (Relatively so) for a week on our Little Whit.

Here is a piccy of the little guy doing its thing after about a weeks burn time.
Today it will get a cleaning.

I gave up being anal about the glass many many years ago.
 

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Here is a picture of the glass after one day of cleaning. Seems a lot of folks are having this problem. Wonder if Harman would address the issue or comment.


I know, I already said it but that was before I saw your pic. Now that I see your pic it does look EXACTLY like my glass(2 weeks old). Exactly the same. I would love to know the cause of this pattern but as long as it's not caused by a leak and/or messing with my stoves effeciency I can live with it no problem.

At least the whole glass does'nt get "smoked up" like my old(more efficient) 1990 Avalon does. Also, the quality of pellets has a major role in how smoky your glass gets. When I first got my old Avalon I picked up 10 bags(forget the brand) from Home Depot on the way home. I cleaned the glass every single day (really dark, thick buildup) and it took me at least 10-15minutes to get it clean(everyday) with a lot of elbow grease mixed with windex/ash formula. Once I switched pellets(to 100%DougFir) it only took me 20 seconds to wipe off the glass with a paper towell dampened with water.

All in all I love my new XXV-7

it sure is purdy :)
 
I saw some old posts about the glass getting soot on it after a few hours of burning. I have a new Harman xxv and it has happened every day. I am wondering if any found a fix or is it something we just live with.
It looks like an inverted L. Starts in the lower right hand corner and goes up and across the top to the left.

On my Accentra I have found that, over time, using stove top ceramic glass cleaner helps increase the time before the glass gets dirty. I think it fills micro-pores in the glass and makes it just a bit harder for the ash to adhere. It has certainly worked for me if I use it every time I clean the glass.
 
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