Harman Absolute combustion fan noise after cleaning

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NevadaReds

New Member
Nov 7, 2023
4
Nevada Mountains
Hey all! I've put a ton through a year old Harman Absolute 43 with no issue, but it came time for the "full cleaning" so I did it and now I've got a weird noise. The only thing I think I did wrong was that I didn't shut off the combustion fan in the menu first, but it certainly wasn't spinning or anything when I went to clean it.

So I put it all back together and I get a every-few-seconds noise out of the combustion fan now. What I've learned:

  1. If I take the combustion plate thing off the back and put the blower to full (3k rpm), no noise. As I put the plate closer, and when the plate on, it gets noisy.
  2. If I have the plate on and have the combustion fan at minimum RPMs, no noise.
What the heck is it? I went through with a paint brush and really cleaned everything, the fan seems to spin perfectly smoothly in both directions, no drag or clicking. It doesn't wiggle.
 
Also as an update, once it got past the first ~30 seconds of being on it's quiet again, I'm assuming the RPMs dropped off and it's low enough now that it's not an issue.
 
What was the outcome of your issue?
Woke up to mine being noisy this am. Think I'll try cleaning and putting a little oil on it.
Or maybe just go ahead and order a new one as stove is 12 years old now.
 
So mine was the fan, and it eventually grenaded and needed to get fully replaced along with the motor, the whole thing totaled $900. If you can just replace the fan before it damages the motor I'd highly recommend it. When this stove works it's amazing but for our next house I'm just going back to wood.
 
Thanks for the update. I'll take mine apart tonight and clean it. Surprised your fan grenaded they seem pretty sturdy when I clean it.
 
Thanks for the update. I'll take mine apart tonight and clean it. Surprised your fan grenaded they seem pretty sturdy when I clean it.

Yeah, same. Check it out, you can see one of the fins torn/bent.

[Hearth.com] Harman Absolute combustion fan noise after cleaning
 
Took mine apart and cleaned/oiled it. Suspect it is the bearings going out.
Ordered a new motor.
My XXV fan blades look shorter and sturdier than your model.
They look like this.
[Hearth.com] Harman Absolute combustion fan noise after cleaning
 
Installed new combustion fan, new one is very quiet.
This is the one I bought from ebay.
I'll see if I can find new bearing for the old one so I'll have a spare.