Osburn 2200 - fan too noisy

[mlaird]

I have an Osburn woodstove insert, which I think is a 2200 model. Overall, I like the stove and it works quite well. My one complaint is that the fan is annoyingly noisy, especially if I'm sitting in my favorite chair that's right next to the stove. With the fan off, not much heat makes it into the room, but with the fan on, I can't listen to music well and have to turn up my TV.

Osburn's parts lists identify their blower as a 44070 "Crossflow blower," and it's a single motor, long, skinny squirrel cage design. This site's picture looks like what's in my stove (at least without taking mine all apart):

Osburn, Cross Flow Blower Single Cage, Motor Only: 44070-AMP

Replacement Osburn Wood Stove Convection Distribution Blower. Service Part 44070 . Stove & Grill Parts For Less Carries A Large Selection Of In Stock, Ready To Ship, Osburn Wood Stove Repair and Replacement Parts. Included Warranty & Technical Support!

pellet-stove-parts-4less.com

Does anyone have any suggestions on how to either quiet down my blower, or replace mine with something that moves a similar amount of air without the droning/whining noise my blower makes? The noise is not the whoosh of air moving. It's a definite pitch due to the design of the blower or something.

 

[begreen]

The first thing to do is clean the blower and blades thoroughly. Dust and hair can cause the fan to be imbalanced. After that, look at how the fan is mounted. If it is loose or a slide-in fit, then sometimes putting a thin wedge under it will stop it from vibrating.

 

[mlaird]

The noise is not just vibration, although there is some of that at higher speeds. It's a whine that seems to be inherent in the design of the fan that causes it to make a coherent pitch as it spins. The tone is somewhere between 500-770 Hz, depending on the fan speed, which is right in the important range for speech and music, making it particularly annoying and problematic.

 

[begreen]

Sometimes, the direction of airflow can cause harmonics. I don't know if that is something that could be tweaked.

The aftermarket blower assembly could have slightly different characteristics, but this might need to be a try and buy situation unless someone has already tried one. They say they have a try and hassle free return policy if it was found to be noisier.

 

[mlaird]

Here's a short video of the noisy fan, with my decibel meter measuring the loudness objectively. I start out with the fan on a medium speed, then turn it down to its slowest speed, then turn it all the way up. I usually don't run it at full speed because of the rattling. I suspect the bearings are getting worn. But the annoyance is the whining or whistling noise that's present throughout. I'm concerned that any new fan will make the same noise, even if it eliminates the rattling at high speed.