UPDATE: New Harman Advance pellet stove, rumbling noise and auger motor noise

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bcb1

Member
Dec 28, 2011
158
WV
Looks like I'm in the same boat as some other Harman owners. I've got the dreaded woofing sound when my stove is burning at a medium to high flame, it sort of vibrates and sounds like a train or a helicopter outside the house. And in addition to that, my auger motor is loud, I read someone else describing the noise as a cheap rotisserie oven motor, and that's exactly what it sounds like. It wouldn't be so bad if it were a constant noise like the distribution fan blower, but the fact that it only feeds once every 5-10 seconds makes it very noticeable.

Very disappointing on a new $3800 stove. My old 2004 Quadrafire Santa Fe was dead silent. Yeah, it was a pain in the rear to have to clean out the burnpot every single day, but it sure was nice to have a stove that was quiet. I'm afraid I've spent a pile of money to get a stove that I don't have to clean as often, yet is driving me crazy with the noises it makes.

So, all you Harman experts:

1. Is there a way to quiet down the auger motor? I see a guy on ebay that sells replacement motors made by a different company for about $130. I don't care about the money, I'd gladly pay $130 for a new auger motor if it were as quiet as my old Quadrafire stove. Would my dealer replace my motor on my brand new stove simply because it's "too loud"?

2. For the stove rumbling, subwoofer sound, what I've done so far is put a piece of foil tape over part of the air intake port. That has calmed down the sound, but it also makes for a lazier flame. Take the tape off and the flame goes crazy, but the rumbling comes back. Arrrrrgh. All gaskets seem okay - door gasket, ashpan gasket, pellet bin gasket. I'm running on inside air, not the outside air kit if that makes any difference.

Help! Any advice is appreciated.
 
I have noticed that mine will do this every once in a while and only with certain pellets. I am running Lignetecs now and have not heard it in the last few days
 
whats the feed rate at? what kind of pellets? There is a 98.7% chance it is NOT the stove
 
Those are my threads you are referring to.

Relative to the woofing, you'll have to stay tuned for that one. Hopefully it's a hopper gasket issue, not an inherent flaw in the design. I've ruled out the lower hopper gasket, but the upper one could be suspect. It's a royal PITA to get to on the XXV, so I haven't had much time to figure out a way to seal it properly. Hard to say, might be inherent in the design because the volumetric pressure for the hopper and the burn area are different causing this anomaly. Now that I have a Skytech thermostat, the stove burns on hi or low, so the woofing is VERY minimal as the flame ramps up.

Gear motor for the auger - yes, it's reasonable to request a replacement if it makes too much noise. IMO, then the combustion and distribution fans are on hi, the auger gear motor should be "invisible" from a reasonable distance. While he's replacing the gear motor, discuss the woofing and see what they say. My dealer and Harman seems to be avoiding it like the plague.
 
I'm using Greene Team pellets from my local stove dealer. Very good in past years, they seem to be a bit smaller and have a bit more ash this year. I got 25 bags of Hamer's Hot Ones with the stove, so I'll try them as soon as I get them delivered.

Feed rate is 4, though I've lowered it to 3 and it helped a little bit but not much, so I turned it back to 4. Putting the piece of foil tape over about 1/2 of the air intake seemed to help the most, it just doesn't burn with that real fast, active flame. It's not real lazy, just not as active as with no tape on the intake pipe. I suppose I can live with it, I just found it rather annoying.

I read in another thread that a guy cured his by replacing the door gasket, and his stove was only a year old. I suppose I could call the dealer for a service call and have them replace the door gasket and check/replace the noisy auger motor at the same time. Another guy said it was his flame guide. I was thinking about putting a small piece of steel behind the flame guide to make it stick out another 1/8 inch or 1/4 inch. Maybe that would be enough to change the flame pattern and keep it from woofing...?

Interestingly enough, when the stove burns for a day or two without cleaning it, I don't notice the woofing nearly as much. I guess the ash builds up and it makes the flames burn at a different rate or angle? I definitely notice it more when the stove is nice and clean, no ashes.
 
Update as of 12/29:

Cleaned out burnpot thoroughly. Set pellet feed to 4, temperature to 70 degrees. Blocked a little less than 50% of the intake air pipe with aluminum foil tape. As of now, the rumbling "train" noise is liveable. It's most noticeable at startup when the fire is big. Once the room heats up, ashes build up in the burnpot and the stove starts to crank down the fire to a smaller flame, the rumble sound is completely gone.

What's not gone is the annoying whrrrr-rrrrr-rrrrr noise of the auger motor. I've got the local Harman dealer coming to look at it on Tuesday next week but I bet he says it's normal. I'm hoping that he might humor me and swap it out with another one, but we'll see.
 
bcb1- I would push hard for him to swap out the auger motor.

Mine became really noisy when my stove was about 2 weeks old. I could hear in turn when I was upstairs in bed.

I pulled it out myself and brought it to the stove shop. Interestingly, it was quiet when it was not mounted in the stove. It seemed like the vibration was resonating when it was in the stove.

Dealer said it checked out normal so I asked him to give me another one just to humor me. The new one was much quieter.
 
Dougsey: Thanks for the advice, I will definitely ask the tech to swap it out. According to the chimney sweep guy that installed my pellet pipe years ago, the tech at the Harman dealer where I got my stove is very good, so hopefully it won't take too much convincing.

By the way, your issue with the auger resonating is the exact same issue I'm having. It seems like it's vibrating, or maybe the sound is bouncing off all the metal nearby. I figure if they swap it out and it helps, great. If it doesn't help, it's not so bad that I can't live with it. In fact if it's no different with the new motor from Harman, I'm going to try one of the motors from Merkle-Korff. There is a dealer that sells them on Ebay for $130. Supposedly built to very exacting tolerances and much quieter. He said he'd even ship it, allow me to install it and take it back if it wasn't quieter. That's a very generous return policy!
 
I've got a older (2005) Accentra and it has rumbled since day one. Mine mostly does it once the stove is hot and idling, mostly after a high/hot burn. My local dealer has been out at least 15 times trying different things to fix it but we were never able to correct it. We have been able to quiet it down by lowering the fan speed at idle, covering the intake with tape, replacing the front panel gasket (not the door), and trying a smaller fan blade. Originally, they had also removed the damper because I have a direct vent (as recommended by Harmon) but now it's no longer recommended. All of these things stopped the rumbling but made my flame lazy and stove inefficient. I had them remove all the modifications, install a new damper, and leave the fan idle speed low.

4 years and tons of wasted time later, Harman finally decided to give me a new stove. I had it for about a week before I got my old stove back. My new stove rumbled worse than my old one and the new direct drive motor was unbearably loud compared to my old chain drive model which I have managed to get completely quiet.

IMHO, I think the rumbling is just a problem with their stoves as I have heard other models in my dealer's showroom do the same thing while I'm there.

Good luck!
 
Matt715 said:
I've got a older (2005) Accentra and it has rumbled since day one. Mine mostly does it once the stove is hot and idling, mostly after a high/hot burn. My local dealer has been out at least 15 times trying different things to fix it but we were never able to correct it. We have been able to quiet it down by lowering the fan speed at idle, covering the intake with tape, replacing the front panel gasket (not the door), and trying a smaller fan blade. Originally, they had also removed the damper because I have a direct vent (as recommended by Harmon) but now it's no longer recommended. All of these things stopped the rumbling but made my flame lazy and stove inefficient. I had them remove all the modifications, install a new damper, and leave the fan idle speed low.

4 years and tons of wasted time later, Harman finally decided to give me a new stove. I had it for about a week before I got my old stove back. My new stove rumbled worse than my old one and the new direct drive motor was unbearably loud compared to my old chain drive model which I have managed to get completely quiet.

IMHO, I think the rumbling is just a problem with their stoves as I have heard other models in my dealer's showroom do the same thing while I'm there.

Good luck!


So it sounds like there really isnt a cure for this illness. I have a 06 I bought used and have tried everything to cure it. I've actually just learned to live with it and just enjoy the awesome heat that it puts out!!!
 
Thanks for the replies. I agree, the rumbling train sound is just something that I'm going to have to live with. I made it better by partially blocking the air intake tube with foil tape, but it still does it sometimes. Not the end of the world or anything, just a little annoying at times.

What I can't live with is the stupid loud auger! The rrrr-rrrr-rrrr grinding noise is driving me nuts. I can hear it from the next room when it runs. And in my bedroom next door, I can even feel the vibration caused by the auger motor running. It's definitely not something that I should have to live with on a brand new $3700 stove.

I read in other threads that some folks have had their auger motors replaced, only to have the 2nd one just as loud as the first one. But then they replace it again, and the 3rd motor is finally quiet. Seems to be a quality control issue with either Harman or the people that make the auger motors. Mine is a Gleason Avery motor.
 
bcb1 said:
Thanks for the replies. I agree, the rumbling train sound is just something that I'm going to have to live with. I made it better by partially blocking the air intake tube with foil tape, but it still does it sometimes. Not the end of the world or anything, just a little annoying at times.

What I can't live with is the stupid loud auger! The rrrr-rrrr-rrrr grinding noise is driving me nuts. I can hear it from the next room when it runs. And in my bedroom next door, I can even feel the vibration caused by the auger motor running. It's definitely not something that I should have to live with on a brand new $3700 stove.

I read in other threads that some folks have had their auger motors replaced, only to have the 2nd one just as loud as the first one. But then they replace it again, and the 3rd motor is finally quiet. Seems to be a quality control issue with either Harman or the people that make the auger motors. Mine is a Gleason Avery motor.


I agree, mine is rather loud too. You've got me thinking about buying one of the other brand motors from ebay to try.
 
Dougsey said:
bcb1- I would push hard for him to swap out the auger motor.

I pulled it out myself and brought it to the stove shop. Interestingly, it was quiet when it was not mounted in the stove. It seemed like the vibration was resonating when it was in the stove.


Dougsey: Was the auger motor hard to remove? I can definitely take the side panel off and see the motor. I only have a limited amount of space on the left side of the stove to work, would I need to disconnect the pipe and move the stove in order to get the auger motor off, or is it something that you can easily do with the stove in place?
 
PJPellet said:
bcb1 said:
I agree, mine is rather loud too. You've got me thinking about buying one of the other brand motors from ebay to try.

PJPellet: The Harman dealer is coming to check mine out today, hopefully he'll have an extra auger motor to swap in there and we'll see how that goes. If it's not any better, then I'm definitely going to order the Merkle Korff motor from the guy on ebay. It'll be well worth the $130 to have a quiet auger motor.
 
I agree. Besides the auger motor the stove is quiet. It would be great to fix that issue. Keep us posted. Good Luck!
 
Update: Harman dealer tech was here today and I really like him, he's a great guy. He said the auger sounds pretty normal to him, but that he would call Harman and get it replaced under warranty. I made him a deal: he gets a new motor from Harman, I'm going to buy the Merkle Korff motor off the guy on ebay and I'll have it here for him when he comes back to install my new Harman motor. If the new Harman motor makes the same amount of noise as the old motor, he'll swap in my other motor and we'll see if that one is any better.

He said changing out the auger motor is a breeze, it's only held in by one bolt so it only takes a couple minutes. No need to move or disconnect stove.

As far as the rumbling "subwoofer" noise (a totally seperate issue), he said that Harman tech support usually sees that issue on insert stoves. They say on some of them, the rumbling is loud and powerful enough to actually feel in the next room, literally like a train right outside the door. Mine isn't that bad. On inserts, they say it's caused by the cold air in the chimney versus the warm air in the pellet pipe, and the fix is to insulate the pellet pipe with high temperature insulation wrap. Mine is a free standing Advance stove, but my pellet pipe does run through about 12" of unheated ceiling space before it exits the roof. Not real easy to get to without totally disassembling the pipe, wrapping it, and putting it all back together.

First thing he's going to try is replacing the pellet pipe rain cap on the outside, he said mine is the wrong style and it's blocking too much airflow. If that doesn't work, then he'll either insulate the pipe in the unheated chase, and/or replace the existing 3" pellet pipe with 4" pellet pipe.

I really like how he isn't just shrugging off the issue, he is genuinely interested in helping get it fixed.

Oh, and I have my old top vent adapter off my Quadra Fire stove that I wanted to put on my new Harman stove. It has this nifty little latch door at the bottom that allows you to open it up and suck the ash right out of the pellet pipe at the very bottom, right where it all accumulates. Very easy to clean out the pellet pipe that way. Only problem is, both the Quadra Fire adapter and the Harman stove pipe are exactly 3" in diameter. He's going to fabricate a heavy metal sleeve that will slide over each piece to join them together, and fabricate brackets to secure the adapter to the back of the stove. Again, this guy is really interested in making his customers 100% happy.

So - no fix as of yet, but I'm very optomistic that we'll get it tracked down and solved - both the auger motor noise and the rumbling subwoofer noise.
 
bcb1 said:
Update: Harman dealer tech was here today and I really like him, he's a great guy. He said the auger sounds pretty normal to him, but that he would call Harman and get it replaced under warranty. I made him a deal: he gets a new motor from Harman, I'm going to buy the Merkle Korff motor off the guy on ebay and I'll have it here for him when he comes back to install my new Harman motor. If the new Harman motor makes the same amount of noise as the old motor, he'll swap in my other motor and we'll see if that one is any better.

He said changing out the auger motor is a breeze, it's only held in by one bolt so it only takes a couple minutes. No need to move or disconnect stove.

VERY interested in how this turns out. I almost did the same thing and might still do this if the 3rd gear motor doesn't solve the racket! Please keep us posted as I know you will. :)

bcb1 said:
As far as the rumbling "subwoofer" noise (a totally seperate issue), he said that Harman tech support usually sees that issue on insert stoves. They say on some of them, the rumbling is loud and powerful enough to actually feel in the next room, literally like a train right outside the door. Mine isn't that bad. On inserts, they say it's caused by the cold air in the chimney versus the warm air in the pellet pipe, and the fix is to insulate the pellet pipe with high temperature insulation wrap. Mine is a free standing Advance stove, but my pellet pipe does run through about 12" of unheated ceiling space before it exits the roof. Not real easy to get to without totally disassembling the pipe, wrapping it, and putting it all back together.

First thing he's going to try is replacing the pellet pipe rain cap on the outside, he said mine is the wrong style and it's blocking too much airflow. If that doesn't work, then he'll either insulate the pipe in the unheated chase, and/or replace the existing 3" pellet pipe with 4" pellet pipe.

I really like how he isn't just shrugging off the issue, he is genuinely interested in helping get it fixed.

Oh, and I have my old top vent adapter off my Quadra Fire stove that I wanted to put on my new Harman stove. It has this nifty little latch door at the bottom that allows you to open it up and suck the ash right out of the pellet pipe at the very bottom, right where it all accumulates. Very easy to clean out the pellet pipe that way. Only problem is, both the Quadra Fire adapter and the Harman stove pipe are exactly 3" in diameter. He's going to fabricate a heavy metal sleeve that will slide over each piece to join them together, and fabricate brackets to secure the adapter to the back of the stove. Again, this guy is really interested in making his customers 100% happy.

So - no fix as of yet, but I'm very optomistic that we'll get it tracked down and solved - both the auger motor noise and the rumbling subwoofer noise.

Hmmm, this makes no sense to me. Does your flame "quake" when it makes with woofing sound? If so, that would lead me to believe this is a stove pressure issue, not a chimney insulation issue. I like his enthusiasm, and, maybe this does happen with inserts, but we're talking about something different, I believe.

I have a simple up and out vent (Tee, 5' vertical, 90, 2' horizontal) and I've had 2 different brands of vent pipe (Duravent Pro and Selkirk DT -currently), both 4 inch. The woofing between the 2 pipe types is identical.

Sorry, but on a freestanding stove, with a 12" uninsulated section, their explanation sounds like a wild goose chase to me. If his solution does fix your problem (and I hope it does), than there's more than 1 source for the woofing...
 
I'm interested in finding out if the insulation does anything for you too. I have 4" Selkirk venting like what is advertised at the top of the page. It carries the intake air in a larger pipe that encases the exhaust. I just have mine directly vented out the side of the house with no rise. We tried a rise and restricting the exhaust but that didn't seem to help either.
 
Darn it, I was thinking the same thing when he explained the woofing sound being caused by the pipe going through a cold air space. Seemed like it just didnt make sense to me either, cause when I crack the door open or even the ash bin open just a little bit to relieve the pressure, the woofing goes away. I've sort of resigned myself to living with it. Luckily mine only does it when the stove is really clean and the flame is medium to large. After building up ash it doesn't woof nearly as much.

Still, I'm hopeful about getting a quiet auger motor. Looks like it will be 7-10 days so I'll post an update when it's done.
 
Auger Motor Gear Noise: The easy fix. Auger motor is removed by unpluging the stove. Removing the right hand bottom side plate by loosening the screws. Disconnect the two wires going to the motor. Using a 1/2" wrench or socket loosen the one bolt that connects the motor to the auger and slide it off.
Install in reverse order.

Set the motor on a flat surface. Remove the 2 screws that hold the motor to the gear box.
Carefully pull the motor up away from the gear box.
Remove the 4 screws holding the lid on the gear case. Carefully remove the top cover. Using high temp grease (same stuff the auto parts store sells for wheel bearings) scoop a good portion using a piece of cardboard and smear it over the gears. Take care not to move the gears out of position.
Replace the cover and reinstall the motor to the gear box.
Re install the gear motor to the auger and reconnect the 2 leads. Re install rear cover and retest.

That should take care of the motor noise. Cost $4 - high temp grease 45 minutes

Air noise and burn problems: 1st install a proper OAK (outside air supply). That will cure 80% of no oak issues and save you a lot of $. Otherwise don't complain.
 
Funny, I thought I might be going crazy! My new stove is making the same noise (like a train) every once in a while. It must be a stove issue as I had an Englander insert in there for 2 years that never made that noise. I kept the blockoff and the pipe the same, all the installer needed to do was drop in the new insert.
 
I have a 2003 advance that would rumble at random, heres what I found out so far, I have the stove set to room temp and feed rate at 3. I have a 4' straight run with a 45 deg end cap. I also have the wall thimble with the OAK built into it. I have have run about 8 diff brands of pellets so I can rule out its the type of pellet making that sound. I also thought it might be caused by the wind blowing over the top of the pipe but ruled that out when its happened and there was no wind blowing. I will say the rumble only seemed to happen after the stove was running at least 24hrs, here is what I did so far. I replaced the door gasket but I am not sure if it fixed it or not because the problem was always random. But I did notice that when ever I opened the feed hopper door to load more pellets I could almost duplicate that sound just not as loud. I replaced the hopper gasket and to date I have not heard the rumble, So at this stage I am thinking the hopper lid was never sealing 100%? If the stove does decide to rumble again I will replace the ash pan gasket next. Also when ever I do a stove cleaning I always use a nail to make sure each and every hole in the burn pot is free and clear of carbon, it might be worth a shot to make sure all the burn pot holes are opened fully. I have also made sure the ash pan gasket is always clean and not covered in ash. I hope this helps some one.
 
Superchips: thanks for the advice on greasing the gear motor. I was considering doing that - but since my stove is only a couple weeks old I'm going to go with the dealer's offer to replace it for free. If the new motor makes just as much noise I'll probably disassemble and grease it as you suggested. Seems like an easy enough fix.

Regarding the OAK, I was thinking about trying it on a temporary basis as a test. Get a piece of long flex pipe and running it outside - just leave the door propped open enough to get the pipe through it - and see if that helps the rumbling. If it helps, then I'll pop a hole through the wall and do it proper.

FMSM: My old Quadra Fire Santa Fe never rumbled either. Just my new Harman Advance that it replaced. And just like your install, all my installer had to do is pull out my old stove and put the new one in it's place. The only thing he had to change was a small section of pipe since the Harman's outlet is lower than the Quadra Fire's outlet.

NAMZ111: Interesting that yours rumbled when you opened up the feed hopper door. Mine does the opposite, it stops rumbling when I open up the hopper door. It also stops when I crack open the front door or the ash bin door. It's like there is so much vacuum in the stove, just relieving that pressure a little bit stops the rumble.

After talking to the Harman tech yesterday, clearly the issue is well known by the folks at Harman, but maybe there is no definitive fix across the board on every stove. My tech has been to the Harman training classes and he seems very well versed in the stove's technology.
 
bcb1- Please keep us updated on how it goes.
 
I definitely will update as soon as I get my new auger motor installed. I'm going to try and convince him to leave the old motor so I'd have a backup - I'm not sure if he can do that or not. I'd like to be able to have an extra motor that I could disassemble, add some grease inside the motor gears and then put it back in the stove and see if that quiets it down.

Also, I just ordered an OAK from ebay, $51 delivered. The Harman tech said installing outside air might help with the woofing and definitely would not hurt. The threads on this site mostly lean towards recommending OAK, in that it makes the stove run more efficiently and reduces or stops drafts inside the house. So I figured for $50, it was worth trying.
 
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