Accentra Clinkers

[burns291]

My accentra is 2 winters old. I have only ever bought premium grade pellets, maybe 4-5 different mfg'ers. Since week one clinkers have been a major issue.
They grow fast and thick. I gave up scraping and now use a sharp chisel aggressively every 1 to two days.
The stove receives maintenance by me as outline in Harman manual. Per my Harman dealer the draft ( white adjustment knob ) is turned/set all the way to the right.
My flue is set up dryer style with an S bend inside to get required ground clearance outside.
I have been looking for ways to reduce the clinker buildup. The only success I have had is by leaving the feeder door slightly ajar. The flame looks lively,with a blue tint. The stove can burn for a week with hardly any clinker buildup. The only downside I have noticed is ashes blow about more and fall outside the ash box.
Leaving the feeder door slightly unsealed is definitely against Harmon guidelines and has given me cause to pause. Is it Dangerous? Does this indicate anouther problem with my stove?

 

[jtp10181]

When you crack that open is there heat coming out (exhaust) or air going in. If there is air going in then have you checked the path air would normally get into the stove, maybe it is blocked or restricted in some way.

 

[iceman]

My accentra is 2 winters old. I have only ever bought premium grade pellets, maybe 4-5 different mfg'ers. Since week one clinkers have been a major issue.
They grow fast and thick. I gave up scraping and now use a sharp chisel aggressively every 1 to two days.
The stove receives maintenance by me as outline in Harman manual. Per my Harman dealer the draft ( white adjustment knob ) is turned/set all the way to the right.
My flue is set up dryer style with an S bend inside to get required ground clearance outside.
I have been looking for ways to reduce the clinker buildup. The only success I have had is by leaving the feeder door slightly ajar. The flame looks lively,with a blue tint. The stove can burn for a week with hardly any clinker buildup. The only downside I have noticed is ashes blow about more and fall outside the ash box.
Leaving the feeder door slightly unsealed is definitely against Harmon guidelines and has given me cause to pause. Is it Dangerous? Does this indicate anouther problem with my stove?

do you mean the hopper door????
if so you probably need to clean the stove
and it could be in your pipe the config of it
how long is your run? and dryer style ? are you using a flexible pipe?
could you post pic?
its probably in the pipe run
your pipe might be running straight to long therefore not giving it enough natural draft

 

[GVA]

Or you could have a weak Comb blower...
Was it draft tested at startup?
And as Ice said what is your vent setup?
Clinkers are a fact of life, even with premium pellets. Are they hardwood pellets? Try softwood premiums it's alot easier to maintain...

 

[burns291]

When you crack that open is there heat coming out (exhaust) or air going in. If there is air going in then have you checked the path air would normally get into the stove, maybe it is blocked or restricted in some way.

The air is going in to the stove.

 

[burns291]

My accentra is 2 winters old. I have only ever bought premium grade pellets, maybe 4-5 different mfg'ers. Since week one clinkers have been a major issue.
They grow fast and thick. I gave up scraping and now use a sharp chisel aggressively every 1 to two days.
The stove receives maintenance by me as outline in Harman manual. Per my Harman dealer the draft ( white adjustment knob ) is turned/set all the way to the right.
My flue is set up dryer style with an S bend inside to get required ground clearance outside.
I have been looking for ways to reduce the clinker buildup. The only success I have had is by leaving the feeder door slightly ajar. The flame looks lively,with a blue tint. The stove can burn for a week with hardly any clinker buildup. The only downside I have noticed is ashes blow about more and fall outside the ash box.
Leaving the feeder door slightly unsealed is definitely against Harmon guidelines and has given me cause to pause. Is it Dangerous? Does this indicate anouther problem with my stove?

do you mean the hopper door????
if so you probably need to clean the stove
and it could be in your pipe the config of it
how long is your run? and dryer style ? are you using a flexible pipe?
could you post pic?
its probably in the pipe run
your pipe might be running straight to long therefore not giving it enough natural draft

Yes the hopper door.
Stove is cleaned per harman spec.'s
The run is short it starts out with two 90's and the uses two 18" pipes too go outside.
What do you want to see in picture? Also I do not have a lot of experence with pic's.

 

[burns291]

Or you could have a weak Comb blower...
Was it draft tested at startup?
And as Ice said what is your vent setup?
Clinkers are a fact of life, even with premium pellets. Are they hardwood pellets? Try softwood premiums it's alot easier to maintain...

comb blower, I am not sure of its exact function. I will have to look at manual to see what it does for sure. Does it draw air into stove to provide combustion air.
I suspect that not enough air is being drawn into unit to provide proper combustion. But given the short run of my pipe, with no upward pipe, I was wondering if the draft was poor. No I did not have draft tested at startup. I did have my dealer out reguarding the feeder chain that was not running true. At that time I asked about clinkers and the draft. He did not test but explained that the white draft control knob when it is turned to the right the most it can go provides maxium draft. I run the stove in this position.

 

[iceman]

My accentra is 2 winters old. I have only ever bought premium grade pellets, maybe 4-5 different mfg'ers. Since week one clinkers have been a major issue.
They grow fast and thick. I gave up scraping and now use a sharp chisel aggressively every 1 to two days.
The stove receives maintenance by me as outline in Harman manual. Per my Harman dealer the draft ( white adjustment knob ) is turned/set all the way to the right.
My flue is set up dryer style with an S bend inside to get required ground clearance outside.
I have been looking for ways to reduce the clinker buildup. The only success I have had is by leaving the feeder door slightly ajar. The flame looks lively,with a blue tint. The stove can burn for a week with hardly any clinker buildup. The only downside I have noticed is ashes blow about more and fall outside the ash box.
Leaving the feeder door slightly unsealed is definitely against Harmon guidelines and has given me cause to pause. Is it Dangerous? Does this indicate anouther problem with my stove?

do you mean the hopper door????
if so you probably need to clean the stove
and it could be in your pipe the config of it
how long is your run? and dryer style ? are you using a flexible pipe?
could you post pic?
its probably in the pipe run
your pipe might be running straight to long therefore not giving it enough natural draft

Yes the hopper door.
Stove is cleaned per harman spec.'s
The run is short it starts out with two 90's and the uses two 18" pipes too go outside.
What do you want to see in picture? Also I do not have a lot of experence with pic's.

if it starts with 2 9o i am sure thats not a good thing BUT it might be ok ..
is it a horizonal run ?
when does it go vertical...with the 2 18 inch pieces?
try closing the hopper door and pressing down on it to see if the fire changes at all
the screws might not be tight enough or that gasket is bad
also try under the burnpot where the ignitor is to make sure thats tight
from my experience the stove can be a little "touchy" when i t comes to cleaning ... i know you are gonna hate to hear this but clean it again make sure you scrape the exchangers (accordian things) really well, as well as the back of the plates when you take them out
also the the fan blades
what kind of pellets are you using?
how far apart are you 2 90s?
is it 90 right in the back up into another to go straight out?

 

[jtp10181]

I think if his problem was exhaust there would be exhaust coming out when he cracks the feeder door, not room air rushing in. Sounds like an air intake issue to me.

 

[burns291]

My accentra is 2 winters old. I have only ever bought premium grade pellets, maybe 4-5 different mfg'ers. Since week one clinkers have been a major issue.
They grow fast and thick. I gave up scraping and now use a sharp chisel aggressively every 1 to two days.
The stove receives maintenance by me as outline in Harman manual. Per my Harman dealer the draft ( white adjustment knob ) is turned/set all the way to the right.
My flue is set up dryer style with an S bend inside to get required ground clearance outside.
I have been looking for ways to reduce the clinker buildup. The only success I have had is by leaving the feeder door slightly ajar. The flame looks lively,with a blue tint. The stove can burn for a week with hardly any clinker buildup. The only downside I have noticed is ashes blow about more and fall outside the ash box.
Leaving the feeder door slightly unsealed is definitely against Harmon guidelines and has given me cause to pause. Is it Dangerous? Does this indicate anouther problem with my stove?

do you mean the hopper door????
if so you probably need to clean the stove
and it could be in your pipe the config of it
how long is your run? and dryer style ? are you using a flexible pipe?
could you post pic?
its probably in the pipe run
your pipe might be running straight to long therefore not giving it enough natural draft

Yes the hopper door.
Stove is cleaned per harman spec.'s
The run is short it starts out with two 90's and the uses two 18" pipes too go outside.
What do you want to see in picture? Also I do not have a lot of experence with pic's.

if it starts with 2 9o i am sure thats not a good thing BUT it might be ok ..
is it a horizonal run ?
when does it go vertical...with the 2 18 inch pieces?
try closing the hopper door and pressing down on it to see if the fire changes at all
the screws might not be tight enough or that gasket is bad
also try under the burnpot where the ignitor is to make sure thats tight
from my experience the stove can be a little "touchy" when i t comes to cleaning ... i know you are gonna hate to hear this but clean it again make sure you scrape the exchangers (accordian things) really well, as well as the back of the plates when you take them out
also the the fan blades
what kind of pellets are you using?
how far apart are you 2 90s?
is it 90 right in the back up into another to go straight out?

Yes it is a horz. run. It starts with a six in straight pipe and the goes into the two 90 deg. pipes. If I remember correctly one ninety is like adding 3' of pipe. but to get enough height outside I had no other choice. The two 18" pipes then connect onto the top 90 to goes outside. as a straight run.

In regards to the hopper door when closed and pressing down on it. The fire will die for a moment, 1/2 a second, and then resume burning as it was previously. What I have been doing is putting a wedge of paper between the hopper door and the gasket to allow air into the hopper. This changes the intensity of the flame. The flames color has more of a blue tint and the flame itself is less like a candle being blown by a slight breeze and more like a flame from a propane torch. The flame seems more focused it becomes smaller and more intense. To me this seems to be a better more efficient flame. The ashes are blown about more and cleaning becomes a little more difficult. However the clinker formed would probably take two weeks or more before they would even begin to approach the levels they do in a day or so when burning hard in the winter . Now I do not wait this long normally before cleaning the burn pot. With the hopper door wedged slightly to allow more air in, the standard harman tool easily cuts the small amount of clinker that may form in a day. But I am worried that this practice may harm the stove in some way, or perhaps even be dangerous. What do you think?

In regard to cleaning I do scrape the exchangers and plates. I normally use the Harman tool supplied in combination with other tools. Sometimes wire brushes and chisel. When I want to detail the exchanger I find a wet soapy rags loosen any creosote buildup that may still be attached, plus it cuts down on the dust released into the room. I use a long pipe leaner to clean the esp probe. On the fan blades a tooth brush, and I clean the pipes a least two times a winter with a flue pipe brush.

I use Energex premium pellets mostly, but have tied others with no more success. The pellets were purchased this summer at $200.00 per ton this summer.

Yes the 90's are attached together and form an " S " shape.

By the way thank you and all the the other for your responses.

 

[burns291]

I think if his problem was exhaust there would be exhaust coming out when he cracks the feeder door, not room air rushing in. Sounds like an air intake issue to me.

Can you expand on this?

 

[GVA]

I think if his problem was exhaust there would be exhaust coming out when he cracks the feeder door, not room air rushing in. Sounds like an air intake issue to me.

Can you expand on this?

I'll try....Something in the intake path is either blocked or dirty.
Air flow path
Combustion blower (comb blower)Starts the airflow
Air is drawn in through the air intake tube (about 2" diameter)
Air flows into the stove by 2 paths
1st is the airwash
2nd in under the burnpot, then through the holes in the burnpot, around the heat exchangers, to the comb blower, and then out the exhaust.

Things to check and questions
Do you use outside air?
how tight is the home?
Is the little flapper on the air inlet opening enough?
Quickest thing is to have it draft tested and then go from there.

 

[burns291]

I think if his problem was exhaust there would be exhaust coming out when he cracks the feeder door, not room air rushing in. Sounds like an air intake issue to me.

Can you expand on this?

I'll try....Something in the intake path is either blocked or dirty.
Air flow path
Combustion blower (comb blower)Starts the airflow
Air is drawn in through the air intake tube (about 2" diameter)
Air flows into the stove by 2 paths
1st is the airwash
2nd in under the burnpot, then through the holes in the burnpot, around the heat exchangers, to the comb blower, and then out the exhaust.

Things to check and questions
Do you use outside air?
how tight is the home?
Is the little flapper on the air inlet opening enough?
Quickest thing is to have it draft tested and then go from there.

The burnpot I know how to maintain. I even have a little cardboard cutout of the boyyom door with a hole in it that when placed in the opening and then putting a vacume to the hole cleans the ashes out quickly. The little hole I keep cleared with a right angled metal pick. However you mentioned the airwash. I have always thought it was associated with the air comeing out the burn pot. I do not remember any place in the manual reference maintence for it. Where does it output from? Is there a Port/nozzel that should be cleaned?
No I do not use outside air. My home was built in 1948, its a " Lustron Steel Ranch, Prefabricated porcelin covered sttel construction. If you look up lustron steel ranches on internet you may find them interesting. The window are orinigal alum. casement style. It does not have major draft but is far from airtight. My dealer discussed how the tightness of the home could affect the stove, so I have some idea what you are getting at. Last winter I cracked a few window to see if that would have any affect on the flame, but did not see any difference in the flame.

I have often woundered about the air flow into stove. The flap on the inlet opens whwn the stove is drawing air, closes when it is not. I do not know how to tell if it is open enough.

Draft test - my dealer shop is some 30 miles distance away. I went with him because he does service what he sells. At the time a dealer that was closer had no auth. repairman, still do not as far as I know. I have some experience with volt-ohm meters. Do you know if draft meters are hard to use?

 

[GVA]

The draft meter is magnehelic. It's pretty simple there is a bolt on the stove that is removed and the tube is inserted and this measures the vacuum (or draft)on the firebox.
Maybe your dealer can lend you thiers or one can be purchased from Grainger.

The flap, when the stove is running push it open farther see if the flame changes.

I guess it is possible that if you have no restrictions that your comb blower is running so fast that not enough air can be drawn through the inlet so when you open the hopper door this added airflow is making the flames look more active

Airwash on mine it is a slot that runs along the base below the glass. I believe yours is holes, as my bro in law's accentra leaves lines in the glass when it starts to get dirty. They really dont require cleaning. But at the end of the season I usually (with the stove cooled off) put the stove in test, this starts the comb blower. And put a shop vac in blow mode and hold it near the air inlet this helps blow out the flyash under the burnpot that you cant reach and also blows air through the airwash.
But I don't think this is your problem. Get the dealer to draft test it
Here is a better cleaning guide than the manual, but it sounds like you know the procedures
http://www.harmanstoves.com/maintenance/accentracleaninginstructions.pdf

 

[burns291]

[quote author="GVA" date="1194719652"]The draft meter is magnehelic. It's pretty simple there is a bolt on the stove that is removed and the tube is inserted and this measures the vacuum (or draft)on the firebox.
Maybe your dealer can lend you thiers or one can be purchased from Grainger.

The flap, when the stove is running push it open farther see if the flame changes.

I guess it is possible that if you have no restrictions that your comb blower is running so fast that not enough air can be drawn through the inlet so when you open the hopper door this added airflow is making the flames look more active

Airwash on mine it is a slot that runs along the base below the glass. I believe yours is holes, as my bro in law's accentra leaves lines in the glass when it starts to get dirty. They really dont require cleaning. But at the end of the season I usually (with the stove cooled off) put the stove in test, this starts the comb blower. And put a shop vac in blow mode and hold it near the air inlet this helps blow out the flyash under the burnpot that you cant reach and also blows air through the airwash.
But I don't think this is your problem. Get the dealer to draft test it
Here is a better cleaning guide than the manual, but it sounds like you know the procedures
http://www.harmanstoves.com/maintenance/accentracleaninginstructions.pdf[/quote

Thanks for the information uour imput is greatly appreciated.

 

[auerdone]

From what I can find out the newer Accentras have extra holes drilled in the back of the burn box to help reduce this. This increases air flow over this area. Pretty much the same thing that is accomplished by leaving the hopper door ajar, but this is much safer and more controlled than leaving the door open. Also leaving the door open reduces overall stove efficiency.

I also believe that the additional air bypass modification (drilling the 1/4 inch hole in the auger housing) that is being done on the older models (that is now standard on the newer stoves) will also cut down on carbon build up.

I am looking for a picture of these holes, and was thinking of drilling some extra ones in my stove.

Does anyone have a photo.