Black on the glass after few hours!

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smg64ct said:
Your flame height looks high.
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My flame height can vary from about an inch to ten or so depending on how the stove adjusts itself. Still don't get the soot-on-glass buildup as the OP described.
 
I find I get this when I burn the stove on Medium Low or Low for an extended period. . I just think the stove does not burn hot enough at these settings to get a complete burn thus produces a thicker, black ash. I notice this also when I take the baffle off to clean. This also leads to this kind of ash in the exhaust.
The problem is when its warmer out if I burn at a higher heat output like Medium High, the stove is reaching temperature even if I am calling for it to be a couple of degrees higher than I actually want it. So, for me the trade off is a some black build up, which leads to extra cleaning vs that stove starting and stopping all the time which leads to replacing ignitors more frequently. You can try turning down the flame height, which will reduce the amount of fuel going in this might help some.
 
LMPS said:
I find I get this when I burn the stove on Medium Low or Low for an extended period. . I just think the stove does not burn hot enough at these settings to get a complete burn thus produces a thicker, black ash. I notice this also when I take the baffle off to clean. This also leads to this kind of ash in the exhaust.
The problem is when its warmer out if I burn at a higher heat output like Medium High, the stove is reaching temperature even if I am calling for it to be a couple of degrees higher than I actually want it. So, for me the trade off is a some black build up, which leads to extra cleaning vs that stove starting and stopping all the time which leads to replacing ignitors more frequently. You can try turning down the flame height, which will reduce the amount of fuel going in this might help some.
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I don't know your stove but it sounds like not enough air at low burns. Mine regulates automatically but can't you lower flame and keep air high? Quality of the flame will tell you if you are doing well. You want blue to light yellow and short. Oh and as for igniters. I've replaced one in seven seasons running in room temp mode.
 
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LMPS said:
So, for me the trade off is a some black build up, which leads to extra cleaning vs that stove starting and stopping all the time which leads to replacing ignitors more frequently. You can try turning down the flame height, which will reduce the amount of fuel going in this might help some.
Click to expand...
I have been running my MVAE on manual, with a one degree deadband, heat output medium to high (depending on weather) and flame height 3 to 5 (depending on weather). I am still on the same igniter.
I really believe that the concern over burning out igniters goes back to when the MVAE's had a higher Wattage igniter. With the lower Wattage igniter, I wouldn't sacrifice performance of the stove to safeguard the $29 igniter.
 
Cleaned my flue today..about the 15-20 bag mark...
 

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F4jock said:
Unless of course you have a Harman. :)
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Oh, how did I forget that????/ >>>> today's posts >>> 'Harman Igniter', 'Harman Accentra troubleshooting help', 'Stove (Harman) just stopped out of nowhere', 'Harman 6 blink part-time problem', 'Harman P43 Problem'......... Yep, set and forget..... :p:cool:
''
 
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tjnamtiw said:
Oh, how did I forget that????/ >>>> today's posts >>> 'Harman Igniter', 'Harman Accentra troubleshooting help', 'Stove (Harman) just stopped out of nowhere', 'Harman 6 blink part-time problem', 'Harman P43 Problem'......... Yep, set and forget..... :p:cool:
''
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Ain't it interesting that many of these problems turn out to be operator error? And that when there's a design problem Harman sends people to repair it no charge? :p:cool::p

There IS a learning curve with anything complex. Heck, my Galaxy S5 has a manual that thick, ditto my 2014 Escape, and yet another for the My Touch and yet another for the navigation system, but if one reads and comprehends them they work fine too. . . . and they do amazing things that I never knew they were capable of. . . .

My Harman just went five weeks between cleanings, in room temp, burning 24/7 and it could have gone more. Including the weekly glass cleanings and occasional firepot scrapes that total time breaks down to about 15 minutes maintenance a week. It eats every pellet I throw at it while adjusting itself to maintain 69 to 70 F in the room without me messing with dampers, draft adjustments and feed rates. No smoke in the room, no hopper fires, no drama, just one igniter replaced in seven heating seasons. When I clean it at season's end there are few fines in the fines box and little ash in the exhaust. If I put it back together per instructions I have no problems. As I said, reminds me of my refrigerator: It's there and it works. :)
 
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F4jock said:
My Harman just went five weeks between cleanings, in room temp, burning 24/7 and it could have gone more. Including the weekly glass cleanings and occasional firepot scrapes that total time breaks down to about 15 minutes maintenance a week. It eats every pellet I throw at it while adjusting itself to maintain 69 to 70 F in the room without me messing with dampers, draft adjustments and feed rates. No smoke in the room, no hopper fires, no drama, just one igniter replaced in seven heating seasons. When I clean it at season's end there are few fines in the fines box and little ash in the exhaust. If I put it back together per instructions I have no problems. As I said, reminds me of my refrigerator: It's there and it works.
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I could say pretty much the same thing of my Mt. Vernon AE.
It seems that there are two classes of pellet stoves. Those with simple minded control systems, poorly thought out mechanisms and marginally designed combustion systems on the one hand. Then there are the stoves that do their jobs so consistently, and so well, that we forget the sophistication of the Engineering that went into them.
Buying quality is like buying oats. If you want nice, clean, fresh oats, you have to pay a premium price for them. Of course, if you are willing to put up with oats that have already been through the horse, they come cheaper.
I hope I haven't offended anybody with my opinions here. I'm not a snob, I recognize that the low end stoves have their place in the world, in fact I own one. I just appreciate the quality in design and construction of a quality product.
 
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Harvey Schneider said:
I could say pretty much the same thing of my Mt. Vernon AE.
It seems that there are two classes of pellet stoves. Those with simple minded control systems, poorly thought out mechanisms and marginally designed combustion systems on the one hand. Then there are the stoves that do their jobs so consistently, and so well, that we forget the sophistication of the Engineering that went into them.
Buying quality is like buying oats. If you want nice, clean, fresh oats, you have to pay a premium price for them. Of course, if you are willing to put up with oats that have already been through the horse, they come cheaper.
I hope I haven't offended anybody with my opinions here. I'm not a snob, I recognize that the low end stoves have their place in the world, in fact I own one. I just appreciate the quality in design and construction of a quality product.
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X2
 
I think that F4 hit the nail on the head when he said 'operator error'. Clearly this year's posts are a testament to that! You can have a $5K Harman or a $1K Englander and if you have no idea of what you are doing, it makes no difference. It AIN'T gonna run! NOW if you DO know what you're doing, read the manuals, and have some mechanical/electrical ability, then you can get years of service out of EITHER stove. Sure one will do everything but wipe your butt, but you paid for it. No problem there if that makes you happy.
I read a post over on the wood burning forum where MANY people were debating whether or not cutting/splitting/hauling/stacking/hauling/burning was work or enjoyment. The same goes for pellet stoves. If you don't like to spend 5 minutes communing with your stove once a week, then spend that extra $4K. It makes no difference to me. :) The bottom line is IF YOU DON'T KNOW HOW A PELLET STOVE WORKS AND HOW TO MAINTAIN IT, THEN DON'T BUY ONE - PERIOD!
 
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Harvey Schneider said:
I have been running my MVAE on manual, with a one degree deadband, heat output medium to high (depending on weather) and flame height 3 to 5 (depending on weather). I am still on the same igniter.
I really believe that the concern over burning out igniters goes back to when the MVAE's had a higher Wattage igniter. With the lower Wattage igniter, I wouldn't sacrifice performance of the stove to safeguard the $29 igniter.
Click to expand...

You are correct, I do have the low wattage igniter now and have not burned through one yet. I would agree burning like you will produce a hot enough burn so you get a more complete burn and the stove does not get the black build. What are you using for room differential? The other question I have is do you burn more pellets burning this way vs burning longer on a lower setting?
 
LMPS said:
You are correct, I do have the low wattage igniter now and have not burned through one yet. I would agree burning like you will produce a hot enough burn so you get a more complete burn and the stove does not get the black build. What are you using for room differential? The other question I have is do you burn more pellets burning this way vs burning longer on a lower setting?
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The differential or deadband is set to one degree. I was tempted to set it to 1/2 degree, but I am quite comfortable with the one degree setting, nothing to gain by it.
I don't really have a feeling for whether I am burning more this way. My pellet consumption has increased over the three heating seasons as I got more comfortable with relying on the pellet stove as my primary source of heat, so year to year comparison is difficult. I am sure that the efficiency drops when I have the stove max'd out, but there are days when the full capacity of the stove is required. My goal is to keep the house comfortable using a lower cost, renewable energy source.
 
Actually the hotter the stove runs, I think efficiency is gained, because metals seem to transfer heat faster the more temperature rises, but I could be proven wrong.
 
hyfire said:
Actually the hotter the stove runs, I think efficiency is gained, because metals seem to transfer heat faster the more temperature rises, but I could be proven wrong.
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Yeah, the bigger the delta T the better the heat exchanger works but I think that combustion may be sub optimal. I don't really know, but I see a lot of flame reaching for the vent. Makes me think that I'm putting a lot of heat out the vent.
 
My flame seems to spread forward toward the glass with the intake damper not open far enough. The window seems to get a dark pattern in a shape of the lower portion of that flame. When I give it more air, the flame seems to stand more straight up and the window stays cleaner. I try to run it with intake air set to provide a higher, more vertical flame, but not to the extreme of a blowtorch effect. The window still picks up light gray ash, probably not the greatest pellets. Getting excellent heat, though. I'm still experimenting with pellet brands.

Hotter fire requires more fuel, creates hotter exhaust, efficiency depends more on stove and vent design, but probably varies a little with burn temp.
Heat transfer does increase with greater delta T between the exchanger and room air.
 
hyfire said:
Actually the hotter the stove runs, I think efficiency is gained, because metals seem to transfer heat faster the more temperature rises, but I could be proven wrong.
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The hotter it runs doesn't necessarily mean you're transferring more heat more efficiently IMHO. You have to have sufficient air flow to REMOVE that extra heat by creating turbulent flow and eliminating laminar flow. Your blower is only going to go so fast and move so much air. If you put even more heat into the heat exchanger, you're overfiring the stove and stressing it above its design limits.
Once again, I suggest that the OP's picture shows he's overfiring the stove according to the manual. which causes the black window.
 
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I have a Breckwell insert with a big glass window. Gets dirty regardless of the pellets, the cleanliness of the stove, or the state of the exhaust and/or intake.

But it does heat great.
 
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