Thumping Noise From Harman P61a

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rico7684

Member
Sep 22, 2010
39
Finger Lakes, NY
I woke up this morning to find my 9yr old P61a making a small thumping noise at regular intervals. I noticed that when the auger turns and feeds pellets it makes the thumping sound. Does anyone know what this might be due to? The stove has worked flawlessly up to this point through many years of hard winters in Western NY.

A forward thank you for any and all help!
 
You're welcome. Appears the pellets (probably a long one) in the fines box were bridged/compacted. Have you noticed a difference in pellet length on the brand that you are using?
 
I am using Easyblaze pellets for the first time, as they haven't been available in my area before. Pellets are fairly uniform in size, nothing too long, or short, but more uniform overall than past pellet brands I've used. The EasyBlaze are the best pellets I've used; burn hot, low ash/fines and burn pot build up is almost non-existent.

Again, thanks for the info!
 
After two days of working properly, the thumping noise came back yesterday. I opened the fines box and there were a few pellets and fines, which I again cleaned out. The stove worked without any noise until late last night and then it was back & has been since. Besides the noise, the stove appears to be working as it should.

Anyone have any other ideas as to what is causing this noise?

Another forward thank you for all help!
 
I feel like I was going to a mechanic. Just before I took off the back panel, the noise stopped. :confused: I watched the auger operate and all appeared normal. Guess I'll just keep an eye on it.

Thanks Dataman for your help and hope you have a good day!
 
No Cats or Dogs in House? If so button it up. Could be just noise from Panels vibrating. I had awful noise from my XXV. It was screws impacting the housing of Distro Fan. Shorten screws after I ordered new fan. Hey I got spare parts. All last year it would buzz when cold, then go away. This year quiet as mouse with Box Fan on his back, but no buzz. Actually pretty quiet on 1/2 speed.
 
No animals in the house. Noise is still gone & I get a buzz on occasion which is normal, but the thump is not. Stove has been very reliable and I am impressed with Harman.

Thanks again!
 
Me too. Been great stove. I replaced BK King with Harmon XXV last May. Except for couple of hickups (Noise on Fan and Poor Air Exhaust in Chimney) been great. We got down to -10f last year and it did the job quite well. I keep wire cloth in pipe that goes thru wall to keep out Stupid Birds. They seem to think chimney is good place for nest. Fall thru and end up in stove. Royal pain to get them out. I just open up the cleanout outside and they fall thru to freedom and don't come inside. I left it in place last year and soot clogged it. Stove got very Black sooty inside. Simple fix.
 
My stove is vented directly through the roof. I had a wood stove prior to the P61a and with a 6' pipe, but was able to vent the Harman with an adapter, so it's a straight pipe. I have gotten birds in it a few times over the summers & one blocked the exhaust fan when I went to use it in the Fall.
 
Take some compressed air and blow the hell out of the fines box while holding a vaccum. This should knock loose any pellets and blow the fines to the burnpot as well. Another thought maybe to ensure the set screw on the auger is tight.
 
Welcome. One more thought. Oil the 2 bushings in the fines box as well. Maybe they are stiff and preventing full movement. Should be another bushing on the outside to the right to oil. Ive used wd40 but prefer 3n1 oil.

Also use the compressed air and blow up underneath the slide plate. Youll be amazed at the amount of dust that will come out from that.

These are things that I do every time when cleaning.
 
It is a gear driven motor for the auger. The clunking is intermittent & I have taken miteclipse's advice & blown air up underneath the slide plate and oiled the bushings. Other than the periodic noise all appears to be working fine.

Thanks to everyone!
 
Sounds like your chain is getting loose. You can try adjusting the tensioner. But it might be time to get a new chain. Might be a good idea to get new gears while your at it. The chain gets loose as it gets old and gets slop bunches up and slips.
 
Harman Auger.jpg
Harman Auger.jpg

The auger motor is a gear driven one as per the photo
 
sounds like its time to sit in back of the stove while in operation to see where the sound is coming from. so many moving parts on a harman and troubleshooting over the net is a tough one.
 
The saga continues. The clunking noise was back this morning, so I pulled the back panels to see if I could find anything out of the ordinary that seemed askew. I then turned the blower fan switch to off to cool off and while it was doing so, I accidentally knocked the plug out of the socket. When I plugged it back in & turned the blower fan back on, the stove will not feed pellets, or ignite & the combustion fan will not shut off after running for over an hour. I unplugged it again, but the combustion fan just keeps running.

Any ideas?