Comfortbilt HP55

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03Jarhead

New Member
Nov 29, 2020
18
Ohio
Anyone else using one of these yet? It’s the first season of use for me and first pellet stove, as we’ve had electric heat the past 7 years. So far I’ve only burned about 10-12 bags of pellets and I’m overall happy with the stove. However...every 30 seconds to a minute there is a loud clunk/knock. It’s seems to be coming from the auger.
From the research I’ve done, this stove seems to share the same auger/auger motor with castle serenity stoves. I found several threads on here with castle owners with the same weird noises, but no updated the thread with any solutions or even if they found the culprit of the noise.
Other than the noise, the stove seems to be working as it should. I called Comfortbilt a couple weeks ago and their Tech suggested loosening the set screw and bearing down on the auger and re tightening the set screw. I attempted to do this but the auger is pretty much bottomed out on the auger motor shaft so really no where for it to go.
Anyone have any suggestions or fixes for the noise? Since it’s running fine is it even worth worrying about or attempting to find a remedy?
 

rich2500

Minister of Fire
Nov 19, 2005
1,393
Berks County PA.
Are you by chance burning pellets with small pieces in them because those small pieces can get wedged between the auger and when it spits it out it can bang.
 
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03Jarhead

New Member
Nov 29, 2020
18
Ohio
I bought a ton of green supremes and a ton from Tractor supply. The green supremes are pretty uniform in size while the TSC pellets are all over the place in size. So yes some of the pellets are very small and some small pieces. Is it ok to continue to use them or will the banging cause problems?
 

SidecarFlip

Minister of Fire
Feb 7, 2010
5,273
S.E. Michigan
Sure you don't have hard carbon build up at the end of the auger tube or in the burnpot if the pot has a stirrer in it?
 

03Jarhead

New Member
Nov 29, 2020
18
Ohio
The pot doesn’t have a stirrer in it. While I’m not 110% certain the auger doesn’t have a carbon build up on it, I have religiously cleaned the stove daily as I did a lot of reading prior to buying and the consensus was these things only run right while clean. I even scrub the entire burn chamber with a nylon brush to eliminate the fly ash buildup prior to starting it daily. Last night I even removed side plate on the rear of the stove and vacuumed the passage ways even though comfortbilt says this only needs done ever half or one ton of pellets.

Last night I ran a timer several minutes. The clunk isn’t at the same spot in the auger rotation. Sometimes I would get a clunk around 30 seconds, sometimes a minute and sometimes up to a minute and a half. No real consistency to it.
 

rich2500

Minister of Fire
Nov 19, 2005
1,393
Berks County PA.
I bought a ton of green supremes and a ton from Tractor supply. The green supremes are pretty uniform in size while the TSC pellets are all over the place in size. So yes some of the pellets are very small and some small pieces. Is it ok to continue to use them or will the banging cause problems?
Do you have the bang when burning both brands of pellets. Your stove is a top feed stove, auger feeds the pellets up the chute then they drop into the burn pot so it wouldn't be a carbon issue. There is normally a flat spot on the auger motor shaft for the auger set screw to tighten against are you sure that set screw is tightened on that flat spot of the shaft.
 

03Jarhead

New Member
Nov 29, 2020
18
Ohio
Well I think it was making the banging noise with the green supremes as well but haven’t used any for the last 5-6 bags, so I can’t say with 100% certainty now. I will try running those thru starting tomorrow and the day after.

It uses a collar for the set screw. The screw goes through the collar and is tightened on the flat spot of auger motor shaft.
 

Mt Bob

Minister of Fire
Oct 31, 2013
3,349
park county montana
I believe your stove has ball bearings instead of bushings.Yes,could be a problem with one of them.Also could be a poorly made auger,or even poorly made auger tube.BUT,I see your auger has a "breaker bar" on one end,usually only seen on corn stoves.Perhaps this is just the nature of the stove.I would call comfortbilt again,they might want to sen you a new auger assembly.
 

03Jarhead

New Member
Nov 29, 2020
18
Ohio
I spoke with Comfortbilt again today. They advised there could possibly be a bearing on top of the auger that is bad or going bad. Advised to pull it and check. If it was bad they would send a new one out. Before yanking the whole assembly I’m going to empty the hopper again and loosen the set screw and put a good amount of pressure onto the auger assembly and and tighten the set screw again. I’ll see if second time is a charm.
 

03Jarhead

New Member
Nov 29, 2020
18
Ohio
Ok, so I did loosen the set screw on the auger bit and put a fair amount of pressure downward on the auger bit before yanking the whole assembly. Got it to move 1/16-1/8 of an inch then tightened the set screw again. It cured the clunking noise for almost 2 hours and now it’s back again. Set screw is still tight. Will update Comfortbilt again tomorrow and see what they say.
 

Mt Bob

Minister of Fire
Oct 31, 2013
3,349
park county montana
Ok, so I did loosen the set screw on the auger bit and put a fair amount of pressure downward on the auger bit before yanking the whole assembly. Got it to move 1/16-1/8 of an inch then tightened the set screw again. It cured the clunking noise for almost 2 hours and now it’s back again. Set screw is still tight. Will update Comfortbilt again tomorrow and see what they say.
Well,I can tell you what I would do.Empty hopper,empty auger.Remove auger motor.Spin auger and see if you feel or hear any roughness.Remove auger.Support it on each end,by the ball bearings.See if it turns/runs true.Check auger tube for signs of wear,in a certain area,usually a very shiny spot.Check auger tube with a straight edge. SO there ya go.
 

03Jarhead

New Member
Nov 29, 2020
18
Ohio
No not really. Could get the noise to go away for about an hour by loosening the set screw on the auger and pushing down on it, but clunking comes right back. Comfortbilt says could possibly be the bearing on top of the auger is bad. At this point it runs so I’ll leave it be till something breaks and then they can replace it. Beats the “take this off and see” method of possibly, maybe trouble shooting.
 

03Jarhead

New Member
Nov 29, 2020
18
Ohio
Also, if the bearing just sits on top of the auger shaft, would it not just act as a spacer essentially? What could be “bad” about it and causing the clunking noise unless it was completely seized up? @JRemington
 

JRemington

Minister of Fire
Nov 4, 2017
710
Belleville New York
Also, if the bearing just sits on top of the auger shaft, would it not just act as a spacer essentially? What could be “bad” about it and causing the clunking noise unless it was completely seized up? @JRemington
Instead of riding “true” it will slip up and down from the pressure of moving pellets. This causes it to jump up and down creating the banging noise.
 

gfreek

Minister of Fire
Nov 5, 2010
1,422
Attica,,New York
Really can't beat that...