harman Accentra Insert, gummy feed issue

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Ranckie

Member
Nov 11, 2006
23
Androscoggin County, Maine
I have the notorious Harman gummy stove issue in the feed area of my Pre 2009 Accentra Insert. I know what the problem is and right now I would just like to know where the most creosote buildup occurs in the feed area, thus jamming when it trys to feed pellets. My guess is that it's in the area just above the auger where the pellets drop down that angled chute through the rectangular opening in the auger tube. I'm thinking it's most likely where the combustion gasses are backing up through the auger tube and condensing on the colder surfaces of the pellet drop area just above the auger. Any suggestions from those that have actually seen the buildup in that weldment would be most helpful. As a short term fix I plan on making a right angled tool from a very long screwdriver to go up into that rectangular area above the auger and scrape it clean to see if it helps. It's only a short term fix because I'll soon be removing the entire feeder weldment to give it a full cleaning, (I've read that boiling water will desolve it) and adition of the Crossover Air Tube Kit that corrects any creosote buildup in the future. This issue all started just last November after 15 years of trouble free use. Thanks.
 
You have to clean from the auger tube all the way up into the hopper, feed trap and all. BUT, if you have insert slid out, do it now, even if you don't do the repair hose kit, as you will be able to burn for quite a while longer. Fairly easy, once you remove auger and the feed slide plate.
 
It looks like the auger tube is about 2-1/4" in diameter so I was thinking that I could put a 90 degree bend on the end of a long screwdriver and use the flattened tip as a scraper. But, you say that it has to be cleaned all the way up to the slide plate from the auger tube so how do you access that with a scraper tip that is only 2-1/4" long; and how do you access that slanted part where the pellets slide down that appears to be about 4" long. It sounds like you have already done what I am about to attempt. And yes, I am planning on using the stove after this cleaning without the air tube until I remove the weldment later on for a really good cleaning. Thanks for chiming in. It is appreciated.
 
By the way, my stove will be pulled out and everything removed like the feed motor and auger assembly. Also, my auger tube is very clean so access with my "hook scraper" should be fairly easy.
 
You have to clean from the auger tube all the way up into the hopper, feed trap and all. BUT, if you have insert slid out, do it now, even if you don't do the repair hose kit, as you will be able to burn for quite a while longer. Fairly easy, once you remove auger and the feed slide plate.
It looks like the auger tube is about 2-1/4" in diameter so I was thinking that I could put a 90 degree bend on the end of a long screwdriver and use the flattened tip as a scraper. But, you say that it has to be cleaned all the way up to the slide plate from the auger tube so how do you access that with a scraper tip that is only 2-1/4" long; and how do you access that slanted part where the pellets slide down that appears to be about 4" long. It sounds like you have already done what I am about to attempt. And yes, I am planning on using the stove after this cleaning without the air tube until I remove the weldment later on for a really good cleaning. Thanks for chiming in. It is appreciated. By the way, my stove will be pulled out and everything removed like the feed motor and auger assembly. Also, my auger tube is very clean so access with my "hook scraper" should be fairly easy. But, how do you reach way up to the top of the angled pellet drop area?
 
The slide plate is removable through the fines box. With that out,auger out, hopper empty, not too hard to clean
 
The slide plate is removable through the fines box. With that out,auger out, hopper empty, not too hard to clean
I have had the everything out several times, slide plate, auger and motor. But I'm curious as to how you can reach all the way up to the top of the feed area even with the slide plate out, or are you cleaning it from the top by sliding something very narrow down the pellet slide area on the left, (from the top). The angled drop area where the pellets slide down appears to be a good 4 inches or so up from the auger tube to the slide plate so I'm thinking that's too far to reach up with a bent screwdriver tip that is only 2" or so long . How can I to reach that high up, is it done using some sort of long stiff brush forced up from the opening in the auger tube? My apologies for these continued questions but I'm just anxious to get my stove back up and running again. Many thanks also for your help.
 
Anything up that high should clean up with soap and water, or mild chemical. Use rags, on a stiff wire, or mechanics "magic fingers" etc. BUT you may have a severe problem. Wet rags pushed through generally works. Good luck!
 
Anything up that high should clean up with soap and water, or mild chemical. Use rags, on a stiff wire, or mechanics "magic fingers" etc. BUT you may have a severe problem. Wet rags pushed through generally works. Good luck!
Thank you. I'll give it a try and will report back to this forum to let everyone know the outcome. I only want to get it running long enough, (two or three months) to get my feeder weldment out. Once I have thaat out of the stove, I'll do a thorough cleaning of the feeder weldment, and add in the crossover air tube. After that it should be good for another 15 years and I can assure you that 15 years from now, at my age I won't be around to worry about it! LOL Thanks again.
 
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You should not have to remove the weldment for any cleaning. They suck to remove/replace. More importantly, get that bypass hose kit and install.
 
You should not have to remove the weldment for any cleaning. They suck to remove/replace. More importantly, get that bypass hose kit and install.
While I have had my auger out (many times) and have looked straight thorough the auger tube to make sure it was clean, I have never actaully looked "up" to see if I could see what size, and where the opening is that the pellets drop down through from above. If you have cleaned the feeder weldment on a Pre 2009 Accentra Insert, and it sounds like you have, can you please tell me how you actually managed to get a wet rag through what has to be a very narrow opening at the top of the pellet drop area, (at the bottom of the hopper) where the slide plate pushes the pellets into the drop area, and down through and out into the auger tube. Or did you just manage to insert and finagle a rag up through the opening in the auger tube, and push it up as far as you could, and shove it back and forth from the top, down.
 
 
Thanks again but I have already seen Vferdman's entire thread and applaud his very excellent explanation of what, and how he did his cleaning, but I'm just not ready yet to douse my stove with hot water, (though I will say it seems he did take all the necessary precautions to avoid future problems). I guess it's safe to say at this point, based on your responses, that you have not personally cleaned a gummy Accentra Insert and that's okay. But, I am looking for advice on hopefully other methods to clean that feeder weldment besides pouring boiling water down the hopper. I have a DVD coming in a couple of weeks that explains step by step how to remove and replace the feeder weldment on my stove and will most likely go that route to do a thorough cleaning, after which I'll do the air bypass modification. In the meantime I am going to try my "quick" clean by reaching up through the shutter openings in the auger tube and cleaning as much as I can that way, at least enough to get my stove running for a few weeks, at which point I'll have the DVD and will continue on to the next step. Thanks again for all your input.
 
Thanks again but I have already seen Vferdman's entire thread and applaud his very excellent explanation of what, and how he did his cleaning, but I'm just not ready yet to douse my stove with hot water, (though I will say it seems he did take all the necessary precautions to avoid future problems). I guess it's safe to say at this point, based on your responses, that you have not personally cleaned a gummy Accentra Insert and that's okay. But, I am looking for advice on hopefully other methods to clean that feeder weldment besides pouring boiling water down the hopper. I have a DVD coming in a couple of weeks that explains step by step how to remove and replace the feeder weldment on my stove and will most likely go that route to do a thorough cleaning, after which I'll do the air bypass modification. In the meantime I am going to try my "quick" clean by reaching up through the shutter openings in the auger tube and cleaning as much as I can that way, at least enough to get my stove running for a few weeks, at which point I'll have the DVD and will continue on to the next step. Thanks again for all your input.
For what its worth, The Accentra insert is the easiest of the harmans to remove and reinstall the feeder weldment.
 
You are right,I have never done it to an insert. But funny thing, the feeder is exactly the same as a free standing Accentra, all P series Harman's, an Advance and XXV. Whether it is an early chain drive, or direct drive.
 
For what its worth, The Accentra insert is the easiest of the harmans to remove and reinstall the feeder weldment.
You are right,I have never done it to an insert. But funny thing, the feeder is exactly the same as a free standing Accentra, all P series Harman's, an Advance and XXV. Whether it is an early chain drive, or direct drive.
Thank you Mt Bob for all of your suggestions; I mean you no disrespect with that question. I'd also like to thank Rickwai for his comment.

A little background information at this point might help to enlighten everyone. I am a retired Industrial engineer (about 45 years) with a strong background in machine tool technology, metal & welding fabrication, hydraulics & pneumatics, and electrical knowledge. If I had the tools, metal, and time, I could build most of the components on that freekin stove but that's for another day (do you see my frustration building here).

Yesterday, I pulled my insert out for the 7th time, and in my case the hearth is very low so my stove sets about 3" off the floor, also keeping in mind that my stove weighs 450 pounds without pellets, and at my age, (80 is now in my rear view mirror :) ), it doesn't slide in and out as easily as it did when I installed it 15 years ago! Here is where everything stands right now. I now feel quite confident after a very close inspection yesterday of all of the involved components that I do not have the gummy stove problem. I now know that whenever I pull out the auger, it's always full of pellets which tells me that the pellets must be sliding down into the auger freely, and everything in and around my slide plate is clean. Yesterday, after sitting there and running the feed system while the stove was pulled out, (I made a jumper that connects directly to the auger motor) I just kept letting it feed pellets while I sucked them out of the burn pot with a small vacuum. After about 10-15 minutes it stopped feeding again.

Frustrated, I first tried to move the Pusher Arm Weldment, that "C" shaped cam piece that moves the slide plate back and forth and surprisingly, it was free and easy to move so I knew that the slide plate was not bound up. Then I tried to turn the auger and found that it didn't want to turn. As I wiggled the auger shaft back and forth, it finally started to move a bit and then moved backwards and finally it became free to rotate. I removed the auger motor and the auger shaft/bearing again, (for the eighth time now) and everything appeared normal, (and yes, the auger bearing turns nice and free like a brand new bearing). I then started to suspect that I had a "weak" motor that didn't have enough strength to shear any pellets that might be caught half way between the shutter opening above the auger tube and the auger, as the auger rotated because to my thinking, it's inevitable that some pellets in any of these stoves don't make it all the way through the shutter opening and will get sheared off as the auger rotates; those 4 RPM gear motors should do that quite easily.

I then put my old motor back in which was still running when I replaced it, but I wanted to rule out the motor because I wasn't aware at the time that these Gleason Avery motors (OEM to Harman), have thermal cut outs when overloaded. I felt that if the motor was jammed and stopping, it may have damaged it so I purchased a new Gleason Avery motor. They are really good motors; they are quiet and made in the USA, not like the other noisy imported pieces of junk. I then ran the same standing test just running the feed system while sucking out pellets and the stove ran for about 30 minutes without stopping. I put everything back together, pushed the stove back in, and started it up. That was about 5:00 yesterday afternoon. At first, it ran normal and then after a few minutes the fire started to die down but never went out, then it would pick back up and it did that for about 30-40 minutes. At this point I'm thinking control board, but after a while it started running normal with a nice steady fire, (we always run our stove on Stove Temp) and it stayed at a steady fire until we shut it off around 9:30 last night. This morning I turned it on around 4:30 a.m. and it ran normal and has been running fine as of this writing. Go figure! Did I (or do I) have a faulty new motor and/or a bad control board? Has the devil taken up residence in my stove?
 
Interesting.
I've always been told it is a really bad idea to continuously run an intermittent duty motor, especially under load.
Now, I have never seen a thermal protector on a auger motor, this would be a mechanical device that opens up, stops motor, then shuts when cooled down. It would be pretty obvious.
Probably Gleason's have "impedance" protection. What this does, is keeps the windings from burning up, if the motor stalls or locks up. It does not stop the motor, that has already happened. Many small motors are built this way, even cheap room fans. SO, in theory, after motor cools down and becomes free, it can still be used as if nothing happened. SO your motor may be fine.
One thing I would try, at this point, get a can of Deoxit f5, and clean/lube the "pots" on the control board, make sure to rotate them as you spray, just like a volume control on a radio or TV(yep,I am showing my age,LOL!).
OK have a good day!!

 
Interesting.
I've always been told it is a really bad idea to continuously run an intermittent duty motor, especially under load.
Now, I have never seen a thermal protector on a auger motor, this would be a mechanical device that opens up, stops motor, then shuts when cooled down. It would be pretty obvious.
Probably Gleason's have "impedance" protection. What this does, is keeps the windings from burning up, if the motor stalls or locks up. It does not stop the motor, that has already happened. Many small motors are built this way, even cheap room fans. SO, in theory, after motor cools down and becomes free, it can still be used as if nothing happened. SO your motor may be fine.
One thing I would try, at this point, get a can of Deoxit f5, and clean/lube the "pots" on the control board, make sure to rotate them as you spray, just like a volume control on a radio or TV(yep,I am showing my age,LOL!).
OK have a good day!!

Hi Bob, You are correct about the protection being "Impedance protected" as can be seen here:


I suspect that my motor was/is fine as you stated because it's still running fine right now. Thanks for the suggestion on the Deoxit F5, I will surely give that a try. Even though it's not likely, is it possible that i did get a "weak" motor. In yesterdays test, the new one is the one that stopped working, and yet my old motor was, and still is running fine. I think I'll gladly pay for shipping to have Gleason Avery check out that new motor to see if it's up to par, just to satify my curiosity. As for your volume control age comment, I'll bet I have you beat; I was playing with the potentiometers on radios when I was about 12 years old! Do you remember when we used to make those "crystal radios" where you had to move that cat whisker around the crystal in order to pick up a station.. Ha, now that's old! Thanks again.
 
Thank you Mt Bob for all of your suggestions; I mean you no disrespect with that question. I'd also like to thank Rickwai for his comment.

A little background information at this point might help to enlighten everyone. I am a retired Industrial engineer (about 45 years) with a strong background in machine tool technology, metal & welding fabrication, hydraulics & pneumatics, and electrical knowledge. If I had the tools, metal, and time, I could build most of the components on that freekin stove but that's for another day (do you see my frustration building here).

Yesterday, I pulled my insert out for the 7th time, and in my case the hearth is very low so my stove sets about 3" off the floor, also keeping in mind that my stove weighs 450 pounds without pellets, and at my age, (80 is now in my rear view mirror :) ), it doesn't slide in and out as easily as it did when I installed it 15 years ago! Here is where everything stands right now. I now feel quite confident after a very close inspection yesterday of all of the involved components that I do not have the gummy stove problem. I now know that whenever I pull out the auger, it's always full of pellets which tells me that the pellets must be sliding down into the auger freely, and everything in and around my slide plate is clean. Yesterday, after sitting there and running the feed system while the stove was pulled out, (I made a jumper that connects directly to the auger motor) I just kept letting it feed pellets while I sucked them out of the burn pot with a small vacuum. After about 10-15 minutes it stopped feeding again.

Frustrated, I first tried to move the Pusher Arm Weldment, that "C" shaped cam piece that moves the slide plate back and forth and surprisingly, it was free and easy to move so I knew that the slide plate was not bound up. Then I tried to turn the auger and found that it didn't want to turn. As I wiggled the auger shaft back and forth, it finally started to move a bit and then moved backwards and finally it became free to rotate. I removed the auger motor and the auger shaft/bearing again, (for the eighth time now) and everything appeared normal, (and yes, the auger bearing turns nice and free like a brand new bearing). I then started to suspect that I had a "weak" motor that didn't have enough strength to shear any pellets that might be caught half way between the shutter opening above the auger tube and the auger, as the auger rotated because to my thinking, it's inevitable that some pellets in any of these stoves don't make it all the way through the shutter opening and will get sheared off as the auger rotates; those 4 RPM gear motors should do that quite easily.

I then put my old motor back in which was still running when I replaced it, but I wanted to rule out the motor because I wasn't aware at the time that these Gleason Avery motors (OEM to Harman), have thermal cut outs when overloaded. I felt that if the motor was jammed and stopping, it may have damaged it so I purchased a new Gleason Avery motor. They are really good motors; they are quiet and made in the USA, not like the other noisy imported pieces of junk. I then ran the same standing test just running the feed system while sucking out pellets and the stove ran for about 30 minutes without stopping. I put everything back together, pushed the stove back in, and started it up. That was about 5:00 yesterday afternoon. At first, it ran normal and then after a few minutes the fire started to die down but never went out, then it would pick back up and it did that for about 30-40 minutes. At this point I'm thinking control board, but after a while it started running normal with a nice steady fire, (we always run our stove on Stove Temp) and it stayed at a steady fire until we shut it off around 9:30 last night. This morning I turned it on around 4:30 a.m. and it ran normal and has been running fine as of this writing. Go figure! Did I (or do I) have a faulty new motor and/or a bad control board? Has the devil taken up residence in my stove?
Not sure if you know, but in stove temp mode the 1-7 on the temp dial is the guage for temperature of the ESP. So maybe on 3 the stove is trying to keep the ESP at 250F . Your feed adjustment still limits max feed rate to achieve that temp. The stove will increase and decrease feed to maintain that Exhaust temp. When the diagnostic tool is hooked to the board you can see what esp temp your set point is and what the esp is actually seeing. With that being said, If the unit is still acting erratic and you ruled out a feeder issue/blockage sounds like a control issue. Which is circuit board and ESP. If you replace the board replace the Esp also. If you have a black wire esp get the red wire one and open the hole up to the next drill bit size. Red is slightly bigger diameter than black. It only takes a second to open the hole up a little. It is not real thick metal there.
 
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Not sure if you know, but in stove temp mode the 1-7 on the temp dial is the guage for temperature of the ESP. So maybe on 3 the stove is trying to keep the ESP at 250F . Your feed adjustment still limits max feed rate to achieve that temp. The stove will increase and decrease feed to maintain that Exhaust temp. When the diagnostic tool is hooked to the board you can see what esp temp your set point is and what the esp is actually seeing. With that being said, If the unit is still acting erratic and you ruled out a feeder issue/blockage sounds like a control issue. Which is circuit board and ESP. If you replace the board replace the Esp also. If you have a black wire esp get the red wire one and open the hole up to the next drill bit size. Red is slightly bigger diameter than black. It only takes a second to open the hole up a little. It is not real thick metal there.

Not sure if you know, but in stove temp mode the 1-7 on the temp dial is the guage for temperature of the ESP. So maybe on 3 the stove is trying to keep the ESP at 250F . Your feed adjustment still limits max feed rate to achieve that temp. The stove will increase and decrease feed to maintain that Exhaust temp. When the diagnostic tool is hooked to the board you can see what esp temp your set point is and what the esp is actually seeing. With that being said, If the unit is still acting erratic and you ruled out a feeder issue/blockage sounds like a control issue. Which is circuit board and ESP. If you replace the board replace the Esp also. If you have a black wire esp get the red wire one and open the hole up to the next drill bit size. Red is slightly bigger diameter than black. It only takes a second to open the hole up a little. It is not real thick metal there.
Thank you Rick. I have to admit that I wasn't fully aware of all that the Harman control board is capable of. I went back to You Tube today and watched a few more videos on the Harman control board and learned some more. With that said, we have been running our stove on Stove Temp since day one, or for 15 years now, but after seeing your explanation and watching those videos today, I realize now that I can do more with my stove than what I thought possible. As far as my pellet jamming issues go, the stove is still running normal as of this writing and the only thing that I did last Saturday after chasing my tail for the past several weeks was put my old auger motor back in and its been running fine ever since. I still believe that I purchased a "rare" bad factory motor. Thanks again for your input.
 
Thank you Rick. I have to admit that I wasn't fully aware of all that the Harman control board is capable of. I went back to You Tube today and watched a few more videos on the Harman control board and learned some more. With that said, we have been running our stove on Stove Temp since day one, or for 15 years now, but after seeing your explanation and watching those videos today, I realize now that I can do more with my stove than what I thought possible. As far as my pellet jamming issues go, the stove is still running normal as of this writing and the only thing that I did last Saturday after chasing my tail for the past several weeks was put my old auger motor back in and its been running fine ever since. I still believe that I purchased a "rare" bad factory motor. Thanks again for your input.
I also wanted to ask but forgot, what is the advantage of using the RED wire probe over the BLACK one? I do know that if I change to the RED I'll have to change the setting of dip switch # 5 from OFF (where it is now for the black) to ON for red according to information I've read of stove forums. Thanks again.
 
I also wanted to ask but forgot, what is the advantage of using the RED wire probe over the BLACK one? I do know that if I change to the RED I'll have to change the setting of dip switch # 5 from OFF (where it is now for the black) to ON for red according to information I've read of stove forums. Thanks again.
Supposedly the red probe is an improvement over the black one. Im not sure what the difference is. I think they claim it is quicker to react to temp change. I know the red is less expensive. They really have the price jacked up on the black one, I guess to make it worth while to keep old style stock
 
I hooked up my DDM to log what each number 1-7 represented in target ESP temperature. Here are my results:
1-251F
2-308F
3-343F
4-378F
5-411F
6-444F
7-470F
I posted this last winter. I did this on my stove with a DDM to see what temp the stove was shooting for at the ESP in stove temp mode.
 
I don't know. But when I rebuilt this Accentra, I ran a new RED one, from control board down, next to the original wires/one, as I suspected i may keep the stove. Well,I did, and it is still running on the original black one, from 2006. I never pull it to clean it, I clean it with a brush from inside. I suppose it will fail, one of these days.
 
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