Ongoing creosote problem

[Ranger Dave]

I have a Harman Accentra. Heats nice, but the problem is a continuous build up of creosote on the door. It's so bad that after one day of use the creosote drips off the door, over - and absorbed by - the door gasket, and puddles under the ash bucket. I was told to run the stove hotter, and I run it at full blast for at least an hour daily. The creosote still builds up. I'm burning Bear Mountain pellets.

I looked last night and the ash bucket was full of smoke and stayed full for about a half hour. There are flames and smoke coming down from behind both sides of the burn pot.

Does anyone else have this problem?

 

[thewoodlands]

I have a Harman Accentra. Heats nice, but the problem is a continuous build up of creosote on the door. It's so bad that after one day of use the creosote drips off the door, over - and absorbed by - the door gasket, and puddles under the ash bucket. I was told to run the stove hotter, and I run it at full blast for at least an hour daily. The creosote still builds up. I'm burning Bear Mountain pellets.

I looked last night and the ash bucket was full of smoke and stayed full for about a half hour. There are flames and smoke coming down from behind both sides of the burn pot.

Does anyone else have this problem?

Dave what is your air setting at and what type of pellets are you burning? We switched to a softwood this year and had to open the air control up more than we did with a hardwood pellet we used in the previous year.


Zap

 

[imacman]

Zap, he said he was burning Bear Mtn pellets....they're some of the best pellets there are. Softwood - Douglas Fir/Red Cedar mix

 

[SmokeyTheBear]

Remember Harmans are pushers and that means they don't always have the correct air/fuel ratio setting as there is not an obvious pellet pile build up like on a puffer.

Likely you have a good case of way too little air. Nothing like an oxygen starved fire for producing 'sote.

Try increasing your burn air.

 

[gbreda]

Remember Harmans are pushers and that means they don't always have the correct air/fuel ratio setting as there is not an obvious pellet pile build up like on a puffer.

Likely you have a good case of way too little air. Nothing like an oxygen starved fire for producing 'sote.

Try increasing your burn air.

Hey Bear

How do you increase burn air on a harman? I just switched from Green Teame (hardwood) to Okies (softwood) and getting soot on a high burn. Can actually see smoke in the firebox. I figured it was an air/fuel issue.

edit: Not trying to hijack the thread, possibly similar issue to Ranger Dave, but no creosote.

The small pot on my control panel was maxed clockwise from the factory.

edit: I did a complete cleaning including esp, exhaust fan, exhause tube and vent pipe cleaning before the changeover

 

[thewoodlands]

Zap, he said he was burning Bear Mtn pellets....they're some of the best pellets there are. Softwood - Douglas Fir/Red Cedar mix

Thanks Macman must of been speed reading! Last year we burned Dry Creek (great pellet) this year we changed to a softwood and will not burn the same softwood next year. I am in the same town has Curran Renewable and will be burning them for next heating season.

zap

 

[newf lover]

I have the same problem with my P68 when I burn super premium, not creosote but black soot. There is no way that I know of to regulate the air on a Harman. The only thing I can think to try is set the feed rate really low, like 2. That seemed to help for me, but I haven't experimented lately because it was a pain to clean.

 

[Ranger Dave]

Dave what is your air setting at and what type of pellets are you burning? We switched to a softwood this year and had to open the air control up more than we did with a hardwood pellet we used in the previous year.
Zap

Bear Mountain, the best. But I don't think I have an air setting on this stove.

 

[Ranger Dave]

Remember Harmans are pushers and that means they don't always have the correct air/fuel ratio setting as there is not an obvious pellet pile build up like on a puffer.

Likely you have a good case of way too little air. Nothing like an oxygen starved fire for producing 'sote.

Try increasing your burn air.

Hey Bear

How do you increase burn air on a harman?

That's a good question. I don't know of any such adjustment.

 

[SmokeyTheBear]

There is both a high and low burn draft adjustment, you have access to the low burn, the factory set the high burn and doesn't provide the information for you to make an adjustment.

The only things you can do to influence the draft on your stoves is to make certain all path ways from air intake to exhaust are clean, all gaskets are good, all doors close tightly, all glass is properly seated, if your house is tight that you use outside air, your house voltage is within specification, all baffles are properly placed and correctly fastened, that your air intake isn't blocked, the back draft damper isn't sticking, and that your combustion blower is running at the correct speed.

It is also possible to influence your draft by having a vertical vent system, etc ... etc ... .

 

[SmokeyTheBear]

Page 12 in the Accentra manual I have talks about low burn draft setting.

 

[Ranger Dave]

Page 12 in the Accentra manual I have talks about low burn draft setting.

Thanks, I'll see if my installer can come out and check that. I'm pretty sure they didn't when they installed the thing.

 

[Ranger Dave]

One more thing. The first year I had this stove this creosote build up didn't happen. The only difference between that first year and the second year is the deflector on top of the burn chamber. I broke the original and bought a replacement. I noticed the build up soon after that. Could there be a connection?

This build up is bad. Sometimes it sticks the door shut.

 

[Delta-T]

to get any residue that has moisture to it you have to be introducing moisture to the system somehow. Either the pellets are moist or excessively humid air, or something. I've never seen any "wet" creosote like parcipitant from pellet burning. You definitely have something going on and I'm gonna say its not the flame guide. Maybe you intake flapper is stuch or blocked, that can cause poor combustion. Tweaking the low draft adjustment is a minute change to the combustion environment.

 

[SmokeyTheBear]

My intent wasn't for the OP to just check the low burn draft but the draft settings in general along with every thing in the air path.

Although considering the climate there the OP may run in low burn most of the time.

 

[stoveguy2esw]

somewhere in the air passage between the intake and exhaust you are likely plugged up , "creosote" as you describe it is from a "smouldering" burn without proper airflow to burn the fuel efficiently. the smoulder creates the liquidic sappy sticky creosote. need to find where the airflow is restricted so badly and releave the restriction

start with checking the flue system , especially horizontal sections and the tee. if they are clear , check the exhaust blower , ash traps in the stove , and also the intake for a blockage , if the intake is from outside and is not screened you may have somthing as simple as a wasp nest inside of it (ive seen that in the past) bottom line though , if it didnt do this last season but it is now then its somthing within the unit which wasnt there before obstructing airflow

 

[Ranger Dave]

Thanks for all the help. I'll be checking the intake better, and sweeping the flue in a day or two. Bad weather now. And I'm using the thermostat, not a slow burn. Between the startup and reaching full heating mode, there is a lot of smoke that slowly swirls around below the window. That makes think there's an airflow problem.

 

[Delta-T]

ranger dave....you have chimney cap up there somewheres?

 

[Ranger Dave]

ranger dave....you have chimney cap up there somewheres?

Yes, the one the installer put on. It's open, clear, with no screen on it.

 

[Ranger Dave]

I've cleaned the stove pretty good. Hooked up my leaf blower to the air inlet and ran it until the soot stopped coming out. Things are going a little better now. There is a lot of smoke coming from behind and below the burn pot. Not just a wisp, but you can see it coming down in a slow moving curtain. The smoke fills up and slowly, very slowly, swirls around inside, and around, the ash bin. I'd swear this smoke is what is causing the creosote buildup. Where's this smoke coming from? How can I stop it?

 

[SmokeyTheBear]

"Hooked up my leaf blower to the air inlet and ran it until the soot stopped coming out."

What? Leaf blower on the exhaust side of things not the intake.

Are you certain that you got that deflector plate in the stove exactly where it should be? When you go to check that make certain the area around it is cleaned.

 

[Lousyweather]

also, you might want to check for airwash leakage from the bottom of the airwash bar......actually was a tech bulletin on it a few years ago......the "fix" was to apply RTV silicone to the seam on the underside of the airwash (right above where you slide the ash pan out of)....seems cool air can leak down onto the lower side of the door from this seam, and, due to the cooler air, creosote could form with the lower temperature. Its not likely the flame guide would cause it....more likely a coincedence. Also, like the stoveguy2ews said above, you might also look for some blockage in the air delivery system......damper door sticking or stuck in the intake for one )as said above), and agreed, it seems to be an airflow issue....still, I'd seal the lower seam in the airwash bar IF its an issue.....

 

[Ranger Dave]

What? Leaf blower on the exhaust side of things not the intake.

Oops. But a lot of soot came out.... all over my car.

Are you certain that you got that deflector plate in the stove exactly where it should be? When you go to check that make certain the area around it is cleaned.

I think that's when my troubles started; when I had to replace that deflector plate. The old one broke when I dropped it on a rock.

 

[Ranger Dave]

also, you might want to check for airwash leakage from the bottom of the airwash bar......actually was a tech bulletin on it a few years ago......the "fix" was to apply RTV silicone to the seam on the underside of the airwash (right above where you slide the ash pan out of)....seems cool air can leak down onto the lower side of the door from this seam, and, due to the cooler air, creosote could form with the lower temperature. Its not likely the flame guide would cause it....more likely a coincedence. Also, like the stoveguy2ews said above, you might also look for some blockage in the air delivery system......damper door sticking or stuck in the intake for one )as said above), and agreed, it seems to be an airflow issue....still, I'd seal the lower seam in the airwash bar IF its an issue.....

The airwash works great and I could find no leakage from underneath. If there were it would be blowing that smoke around. Now this isn't just a few wisps of smoke. It's a heavy smoke that stays in the lower part of the stove. It is billowing down from the bottom and sides of the burn pot. Again, it's not a little smoke, but a lot of thick, greyish white, smoke. I took off the inlet hose and the damper door there moves very easily.

My installer said to "run the stove hotter." That only crystallizes the creosote build up. It does nothing to eliminate the smoke. It doesn't seem right that smoke should be coming down from where it is.

 

[SmokeyTheBear]

If you sucked a lot of soot out from the air intake it must have come from somewhere there shouldn't have been any since it is a straight shot from intake to burn pot.

Now tell us did you also check the gaskets as a bum seal there also causes air flow issues, it would be of the same type of problem that Lousyweather was talking about.

A pellet stove is a very simple device air goes in, the pellets sit directly in the air stream, they burn, the byproducts go out the exhaust. In a positive pressure stove the air is blown into the burn pot in a negative pressure stove it gets sucked through the burn pot. In order to work properly the entire air flow must be unhampered by ash or improperly placed air leaks. There is a very very slight difference in pressure between proper air flow and improper air flow.

This is why a dirty stove is a bad burning stove.