With the cold reality that some day soon the temps would dive, the Pocono was oiled and cleaned today. Reddy to go.
During that cleaning my feeble eyes forced me to take off my glasses to look at the convection blower inlet from 4-5 " inches away (what a sight, the things you see when you don't have a gun). When I really started looking, each 2" long blade of the squirrel cage surprising had a coat of what looked like hardened ash, maybe .030" thick and some of it had fallen off in chunks on random blades. What does all this mean ? Probably nothing except I found a very small balance sheet metal weight on one of the blades suggesting the factory likely does a final balance of the wheel to eliminate any vibes. This suggests it may not take much to get a little imbalance and maybe some noise. Can this imbalance wear out your motor bearings a bit after 2-3 years , hummm ?
So here I am thinking, can this debris cause some sort of imbalance? I'm not sure though it you do have a stove in a semi-dirty environment and your motor vibes starts to increase after 2-3 years , take a REALLY close look at the blower blades, you may see a caked ash debris on them that is not apparent until you REALLY look or brush the blades lightly with your wife's new toothbrush.