Absolute 63 Dirty Glass

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Lifeline25

New Member
Dec 11, 2018
15
Eastern, US.
Hi All,

So my Absolute 63 is a week old today and boy does it crank out some HEAT! We've noticed that the room temp on the control panel and what the room "Actually" is at, is about a 7 degree difference so we've switched to using Constant Burn mode at a 2 or 2.5 setting. Even at that setting we still get a pretty good flame most of the time. My house is new and holds heat very well so if we left the system in Room Sensing mode it wouldn't really run all that much. At constant burn, with the stove running for a few hours, the entire house is around 75-80 depending on the room. And this is a 2000 square foot two story house.

Since the first day we've had trouble with the glass getting really dirty quickly. We don't see any smoke and we are burning good clean pellets. We have the OAK connected and secured on both sides. The stove is in a corner with a 45 and a pass through kit, then a 90 and a 4 foot rise on the outside, terminating with an elbow with a cage for the exhaust.

Within a half hour of cleaning the glass cold and stove start up, the entire top of the glass, nearly half way down, is dirtied up, plus we have pyramid lines coming up from the bottom all the way across the glass. When the stove has been running for about 2 hours or more, the glass is only about 40% visible after that point.

I clean the burn pot twice a day and empty the ash pan every day. We've gone through about 7 bags of pellets now and I even did a full cleaning the other day with the vacuum.

I noticed today when I went to scrap the burn pot that when I opened the door, a small handful of ash came out, and the bottom of the window gasket had ash all over it.

What's up with this overly dirty glass?
 
Okay a few stupid questions? Does the stove have a glasair wash system? Also when you're burning are your creating soot which may not be visible within the fire box area? If you burn on low you're going to get dirty glass. I clean my Ravalli rv100c every 4 to 5 days and basically there's no soot build up on the glass. Now the Glass isn't perfectly clean but all I do is take a wet paper towel with some ash from the fire pot on it wipe it down takes a few seconds wipe it off with another wet clean cloth and then a dry paper towel. And I am running 24/7.
 
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I have Harmon XXV and my glass gets some minor soot. Wipe off with wet paper towel on daily cleaning. No Biggie. I run 4.5 on Feed and Manual Model with Room Mode. We have been having very warm Fall. 40's in Day and 32f at night. When it was cold same on glass. I think it's just part of daily cleaning. Nothing compared to Wood Stove. It would only stay clean if ran full bore hard.
 
I have Harmon XXV and my glass gets some minor soot. Wipe off with wet paper towel on daily cleaning. No Biggie. I run 4.5 on Feed and Manual Model with Room Mode. We have been having very warm Fall. 40's in Day and 32f at night. When it was cold same on glass. I think it's just part of daily cleaning. Nothing compared to Wood Stove. It would only stay clean if ran full bore hard.
I sure would not be happy if I had to do daily cleaning on my Ravalli. Honestly I run the thing 24/7 it has a built-in thermostat and it only needs to be cleaned every 4 or 5 days because that's all the ash box can hold and the glass is really clean even for that length of time.
 
I have an older stove with no air wash . If I run it on low the glass gets dirty with
in 24 hours ( can't see the fire) The hotter I run it the longer the glass stays clean
try adjusting you combustion air may help with a livelier flame to stay clean longer
 
I have had the Absoute 63 for 2 years and the dirty glass is unavoidable after the first 6 hours. I do use cheapo home depot pellets so that is certainly part of the reason. Here is a picture of it today after 4 days:

[Hearth.com] Absolute 63 Dirty Glass


Also, you are definitely emptying the ash pan more than needed. I go about a week or 14 bags between emptying.
 
I had a similar issue with an Absolute 43, Harman could not figure it out and took the stove back. It was burning so dirty that ther was soot coming out the exhaust. I replaced the stove with an Accentra and have had no issues at all.

Before giving up entirely, what are you burning for pellets? Was the stove professionally installed? What is your exhaust set up 3” or 4”?

Can you run the stove hotter? Even if you have to open a few windows try it to see if that makes a difference in your burn.
 
Thanks for all the responses. I am running Hammer Hot Ones. I've been told they are a premium pellet, purchased from the dealer. The reviews online seem to indicate this is a decent grade fuel.

For the temp- yesterday I had the stove running at a 4 most of the day in I'd say more then 50% of the time the flame was hitting the top of the burn area and rolling back down and to the side. The exhaust temp was 380 and that was for a good 8 hours or so. It didn't make a difference on the glass, it sooted up almost instantly.
 
I had a similar issue with an Absolute 43, Harman could not figure it out and took the stove back. It was burning so dirty that ther was soot coming out the exhaust. I replaced the stove with an Accentra and have had no issues at all.

Before giving up entirely, what are you burning for pellets? Was the stove professionally installed? What is your exhaust set up 3” or 4”?

Can you run the stove hotter? Even if you have to open a few windows try it to see if that makes a difference in your burn.


Stove was professionally installed and the exhaust is a 3" set up. I'm wondering is it possible the 4 foot vertical rise on the outside is causing the issue? I wouldn't think so as it was done as per Harmans install guide.
 
I have had the Absoute 63 for 2 years and the dirty glass is unavoidable after the first 6 hours. I do use cheapo home depot pellets so that is certainly part of the reason. Here is a picture of it today after 4 days:

View attachment 236179

Also, you are definitely emptying the ash pan more than needed. I go about a week or 14 bags between emptying.

That's exactly what my glass looks like. I wonder if there is a QC issue.

For the ash pan- i'm just having fun with my new toy. Each time I empty it it's really not even half full.
 
Has been burning for 72 hours now and this is what the glass looks like. What looks like build up on the bottom 25% is actually the ash in the fire pot not on the glass.
 

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Looks normal to me. Wish mine was that clean after 72hrs
 
Looks normal to me. Wish mine was that clean after 72hrs
Yeah I'm pretty happy with the stove and I burn the cheapest pellets I can find at the big box stores. This is my 4th pellet stove and by far the best and probably my last one. I started with a fireplace insert burning cord wood then went to a unit that hooked into my hot water baseboard furnace then an englander 55shp pellet, then to a vistaflame 70k btu pellet stove in basement then an enviro mini in the TV room. Only used the vistaflame 1 season now setting dormant in basement. Had an issue with the mini so bought the ravelli rv100c last season. Best stove by far because it has a built in thermostat burns clean and only clean every 4 or 5 days.
 
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[Hearth.com] Absolute 63 Dirty Glass
I have an absolute 63 installed in corner with 4” pipe going straight up through roof(dealer installed). I have burned about 20-25 bags of premium pellets so far and the glass always clouds up with ash, same as everyone here is describing. I did notice that when running the stove hard the glass stays a little clearer versus running at lower temps. I now have a remote wireless thermostat as before the stoves room temp sensor was overshooting and the stove was always cycling up and down.
Overall I really like the heat it puts out. I have approx 1800 sq foot and it will roast us out. I clean the burn pot once a day (shut stove down) and really scrape the burn pot good to remove carbon build up. I use a standard screwdriver that I bent the shaft to a 45 degree angle so I can really clean/scrape the burn pot throughly. It works way better than tool Harman provides. So far I am very satisfied with my absolute 63 Aside from the glass issue.
 
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I have a Harman Absolute 63. The exhaust pipe has nothing to do with it because mine is run about 14 inches straight out the wall with a 45 degree elbow connected to the end and pointed down to the ground to keep water out and that’s it. The glass gets just as dirty as everyone else says and that’s running it 24/7 and I only clean it when the stove prompts me too.
 

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I am on my third season with my Absolute 63. We burn the cheapest pellets we can find. I maintain my stove based solely on the cleaning prompts. (Scrape burn pot, Empty Ash Pan and Total clean). Piece of advice... get the remote wireless room temp sensor and place about 20 feet from the stove. This is my stove after 5 days of burning.
 

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Not that I am aware of... I have been emailing Harmon repeatedly to ask why there isn't an add on feature with an app to control the stove. "We are working on it" is all I get. Come on Harmon, the stove has wireless capability, digital controls and a USB Slot. Develop a plug in wireless receiver, write an app and let's get on with it. Jeez.
 
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I am on my third season with my Absolute 63. We burn the cheapest pellets we can find. I maintain my stove based solely on the cleaning prompts. (Scrape burn pot, Empty Ash Pan and Total clean). Piece of advice... get the remote wireless room temp sensor and place about 20 feet from the stove. This is my stove after 5 days of burning.

Do you have any issues with ash build up using the cheap pellets? I too have burned some cheap pellets and really the only issue I have was excessive ash. Other than that I love the way the Absolute 63 performs (minus the glass clouding up)
 
No issues... and honestly I can't tell the difference in ash buildup. I empty the ashpan at the same time the stove prompts me to scrap the burnpot, as the stove is cool and it takes all of one minute. This is about once a week.
 
What about the temperature reading? Anyone have an issue with that? I have noticed it’s like mine sticks sometimes. For instance I came home today and the stove is running hard pumping out heat and the touch control says it’s 70 degrees and the thermostat I have in the house that controls my furnace says 84. But once I open the lid and close it again then the stove says 82 degrees.
 
What about the temperature reading? Anyone have an issue with that? I have noticed it’s like mine sticks sometimes. For instance I came home today and the stove is running hard pumping out heat and the touch control says it’s 70 degrees and the thermostat I have in the house that controls my furnace says 84. But once I open the lid and close it again then the stove says 82 degrees.

Nope... never seen this, but I am using the wireless remote room therm placed about 25 feet away from the stove.
 
What about the temperature reading? Anyone have an issue with that? I have noticed it’s like mine sticks sometimes. For instance I came home today and the stove is running hard pumping out heat and the touch control says it’s 70 degrees and the thermostat I have in the house that controls my furnace says 84. But once I open the lid and close it again then the stove says 82 degrees.
I too have the remote sensor but before installing it I did notice that the room sensor on the stove would overshoot. one minute it would read 72 degrees then a minute later it would shoot up to 79. Didn't seem to be too accurate