Harman Advance Excessive cresosote and fires

FredJ

Member
Aug 6, 2006
61
I have a Harman advance since 2005(2006)- A little History before the real question.. This stove was one of the original that had the Smoke in hopper issue which took forever to resolve with "try this" and "try that " ( one false "solution" was I had to change the 3"pipe to 4" and change straight out exhaust to elbow u 4 feet then elbow out another 2 feet). This was by the Dealer with suggestions from Harman who was also working on the issue with other stoves and dealers. They replaced the Stove in 2006 still smoke, eventually added the hose "update" which did resolve that problem. That dealer has since gone out of business.

I use this stove for 100% of heat in my house which is pretty well insulated and it does not run on high all the time- My house is 1450sq feet and I usually use 2 1/2-3 tons of pellets to heat a winter In MA. average 1 bag a day when its in the teens-30's

I have always had a lot of Creosote, in the stove and in the exhaust pipe. I clean evey 3 weeks but still get Pipe fires, mostly in the pipe outside but once in a great while the pipe right off the stove is GLOWING red hot. When I say fire, I mean fire it looks like a jet engine on an aircraft carrier and it spews chunks of creosote. I have tried MANY differt brands of pellets over the years, some bad some "OK" - currently the best results I have are Green Supreme, but stil the problem.
I have had another Authorized dealer check it out, They said everything is well within specs and the stove is in excellent condition. I have contacted Harman who doesnt really seem to care. They are slow to respond and say I get the have a dealer check it out ( which again has been done), they request pictures of the exhaust but no replies when I send them ( and no comment on the video of a fire)
( I tried to add the video here but it is too large)

SOO anyone have any ideas what to do?
 

johneh

Minister of Fire
Dec 19, 2009
2,759
Eastern Ontario
Creosote
I believe in your case is caused by a cold fire (incomplete combustion)
Running the stove on low with not enough combustion air
Is your home real tight?
Do you ever run your stove hot? or it is on low all the time?
Is your stove on a thermostat?
In the 18 years, I have had and used a pellet stove I have never ever
see any creosote
 

FredJ

Member
Aug 6, 2006
61
the dealer used whatever the meter is attached to the stove and all was well within specs,
It does run low often, it has outside air so it can get all the air it wants, and yes my house is tight but with the outside air I dont think that would matter.
it runs hot when it needs to, the house keeps at a constant 70 degrees ( even when its 15 below out). I never change feed rate or temp settings and it uses the temp sensor that came with the stove mounted1/2 way up the wall.
I wish I could upload the video so you could see the flames and ignited creosote blowing out before cooling in globs on the snow
 

jzm2cc

Minister of Fire
Sep 25, 2014
536
Northern Michigan
Prolonged low flame burns can definitely add cresote conditions. If you are not running automatic on/off Room mode maybe try that so it turns off when not needed and ramps up to a large flame when initially heating again. Should help minimize cresote build up.

Also check door gasket for good seal, have seen Accentra's with worn seals that have creosote build up around ash pan and lower door area.
 

SciGuy

Burning Hunk
Aug 17, 2007
170
Constableville, NY
Hi Fred,

I too have experienced a vent fire with a Harman and found it way too exciting. The cherry red exhaust pipe really got and held my attention after hearing what sounded like a freight train running through the living room. My problem stemmed from running the stove in manual mode rather than automatic for a number of days in a row. I was worried about wearing out the igniter by it cycling off so instead allowed the stove to run a super low fire on at any time the temperature was above 25*F or so. With your tight, well insulated house I bet your stove is seldom running very hot. I found a good solution switching to auto ignition and letting the stove cycle between completely shut down and a good solid fire that does not seem to precipitate out any creosote. It made all the difference in the world.

Hugh
 

Don2222

Minister of Fire
Feb 1, 2010
8,549
Salem NH
I have a Harman advance since 2005(2006)- A little History before the real question.. This stove was one of the original that had the Smoke in hopper issue which took forever to resolve with "try this" and "try that " ( one false "solution" was I had to change the 3"pipe to 4" and change straight out exhaust to elbow u 4 feet then elbow out another 2 feet). This was by the Dealer with suggestions from Harman who was also working on the issue with other stoves and dealers. They replaced the Stove in 2006 still smoke, eventually added the hose "update" which did resolve that problem. That dealer has since gone out of business.

I use this stove for 100% of heat in my house which is pretty well insulated and it does not run on high all the time- My house is 1450sq feet and I usually use 2 1/2-3 tons of pellets to heat a winter In MA. average 1 bag a day when its in the teens-30's

I have always had a lot of Creosote, in the stove and in the exhaust pipe. I clean evey 3 weeks but still get Pipe fires, mostly in the pipe outside but once in a great while the pipe right off the stove is GLOWING red hot. When I say fire, I mean fire it looks like a jet engine on an aircraft carrier and it spews chunks of creosote. I have tried MANY differt brands of pellets over the years, some bad some "OK" - currently the best results I have are Green Supreme, but stil the problem.
I have had another Authorized dealer check it out, They said everything is well within specs and the stove is in excellent condition. I have contacted Harman who doesnt really seem to care. They are slow to respond and say I get the have a dealer check it out ( which again has been done), they request pictures of the exhaust but no replies when I send them ( and no comment on the video of a fire)
( I tried to add the video here but it is too large)

SOO anyone have any ideas what to do?
Please post the video on YouTube and post a link here. Thanks
 

FredJ

Member
Aug 6, 2006
61
Prolonged low flame burns can definitely add cresote conditions. If you are not running automatic on/off Room mode maybe try that so it turns off when not needed and ramps up to a large flame when initially heating again. Should help minimize cresote build up.
With your tight, well insulated house I bet your stove is seldom running very hot. I found a good solution switching to auto ignition and letting the stove cycle between completely shut down and a good solid fire that does not seem to precipitate out any creosote. It made all the difference in the world.
I always have had it in room mode, I really dont change any settings at all, just set it and forget it other than cleanings., so it does often run low for very long periods, and except for cleanings, never shuts off from around the 1st week of December to mid April. When its 70 in the house it will run for hours or all afternoon on a low burn. It did that ever since a firmware update back in 2006, before that update when the room hit temp it would shut down pretty quickly, but after the update it will chug along Verrrryy slowly adding a little pellets here and there. So between Jzm2ZZ suggestion and SciGuy it sounds like I need to put in in Stove mode from time to time which I hate to do because the house gets so Hot but maybe that will be the only solution ( unless a firmware DOWNgrade could happem???)
 

Don2222

Minister of Fire
Feb 1, 2010
8,549
Salem NH
Hi Fred
The circuit board for your stove has had many changes and improvements over the years but more specifically if the triacs are worn and not giving the proper voltage to the combustion blower that may cause more build up of creasote and may cause your problem.
In some cases I have not only installed a really good Tripp Lite surge protector but also a Tripp Lite Line conditioner to regulate the voltage to protect all the components in the pellet stove.
Just something to check into. :)
Pic below is my premium voltage protection and regulation setup. :)

One other item I see is that the vertical section of pellet exhaust pipe is outside. Even though that is installed properly and meets code, I never install it like that because the cold air condenses the hot ashy smoke in the pipe and makes it dirty much faster. I always put the vertical rise inside the house for much better performance and 4” diameter venting works better than 3” venting for larger stoves 40K BTUs and higher.
 

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jzm2cc

Minister of Fire
Sep 25, 2014
536
Northern Michigan
Flipping toggle switch from MANUAL to AUTO while using room mode should allow stove to turn off once room reaches temperature given a little bit of idle time. However if it never turns off it makes sense it gets gummed up inside burning so low.
 
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johneh

Minister of Fire
Dec 19, 2009
2,759
Eastern Ontario
That my friend is what burns homes to the ground
Take the advice that shuts your stove down when the temp is reached
Igniters are cheaper than homes!
 

FredJ

Member
Aug 6, 2006
61
OK I get eveyones advice about turning to manual/auto but that is soo much easier said than done! We are not home most of the time- Leave at 6am return 5:45 PM, bed by 9:30 pretty much 6 days a week. so you see there isnt alot of time home to turn it off/ or to manual and let it run, but I'll try to figure something out, probably to manual at 6pm then to auto at 9pm which will shut it down for a while then auto restart as needed for the next 21 hours. I just wish it had a much better thermostat control ( quicker shut down)
But now I have a much better understanding and know that the dealer AND Harman direct dont care and are worth less..

PS, I've never even thought about ignitors, so that was never a concern
 

jzm2cc

Minister of Fire
Sep 25, 2014
536
Northern Michigan
I must be missing something. If stove is left in Auto position on toggle switch, and Room mode on rotary dial, stove should start and shut down based on room temperature. There is no need for human intervention to turn it off. It will restart on it's own also. This assumes a properly running stove
 

FredJ

Member
Aug 6, 2006
61
I must be missing something. If stove is left in Auto position on toggle switch, and Room mode on rotary dial, stove should start and shut down based on room temperature. There is no need for human intervention to turn it off. It will restart on it's own also. This assumes a properly running stove
it does when its warm out 50's plus, but "winter" time it brings the house up to 70 then goes in to what I refer to as shutdown mode when the pellets feed slow and the Dist fan is off, this lasts for a while but it takes so long doing this shut down that the house cools off a couple degrees so it adds a bunch more pellets again and the dist fan comes back on to bring back up to temp (before it has fully turned off) all to start the process over again, and again, and again. If its warm out, it does get to fully shutdown and restarts when needed. As I mentioned before this "shut down" period use to be short before a fimware update was applied, after that it took much longer to shut down. I figured some kind of saftey update to keep the burn from backing into the auger area, but that was just my thought.
 

SciGuy

Burning Hunk
Aug 17, 2007
170
Constableville, NY
it does when its warm out 50's plus, but "winter" time it brings the house up to 70 then goes in to what I refer to as shutdown mode when the pellets feed slow and the Dist fan is off, this lasts for a while but it takes so long doing this shut down that the house cools off a couple degrees so it adds a bunch more pellets again and the dist fan comes back on to bring back up to temp (before it has fully turned off) all to start the process over again, and again, and again.
That's just how our stove runs when placed in auto mode and it works just fine without producing any creosote. It probably does make for a less perfectly even heat but when the fire is burning it's doing so much more intensely without being in that smoldering barely there mode it gets into when just fed a very few pellets for hours on end. Try it for a while and see.

Hugh
 

Washed-Up

Burning Hunk
Nov 5, 2011
170
Kananaskis,Alberta, Canada
I'm wondering if enlarging the holes in the burn pot would help increase the combustion air. Also what size is the piping for your OAK? If its too small in diameter, that may be affecting combustion as well. A video of the fire while stove is burning/working may also help
 

fmsm

Minister of Fire
Dec 12, 2011
946
South of Boston MA
Your stove is too big for the area you are heating. Every few days or at least once a week put it in stove temp auto and crank her up! That will burn off the creosote you are creating with the low burns. I would also consider a premium pellet, Green Supremes are a joke! Get a good Douglas Fir (Northern Warmth purple bag is superior and available in MA) and let her rip for a few hours.
 

heat seeker

Minister of Fire
Feb 25, 2011
3,135
Northern CT
The instructions for my St Croix say to run the stove on high for at least 20 minutes every day, confirming those who say to run it hot frequently.
 

railfanron

Feeling the Heat
Nov 2, 2013
472
Perry MI
Here's a thought. I run my p43 on room temp auto with an external thermostat. Cost around 20 bucks. I leave the temp probe where it is and set the stove temp up to 85 degrees. Then I set my external thermostat to the desired temp. The stove comes on and runs at high flame and once it reaches the set point on the external stat it slowly shuts down. The external stat gives it a wider on/off range and no long low flame burns or restarts in the middle of a shutdown. YMMV
Ron