Sometimes this little black fan will emit a high pitch sound while spinning. If I slow down its spin by touching it with my finger, the pitch is lowered. I've had this Bryant furnace for 10 years and this just started happening. Could the fan be unbalanced? Any ideas on how to fix?
Update: The furnace is a Bryant Plus 80v
thanks
Best Answer
Sounds more like a bearing going bad to me than a balance issue - unbalance is more often a vibration, and to become unbalanced the fan would either need to have a part fall off, or accumulate crud.
"Lifetime lubricated bearings" are a standard euphemism for "we prelubed and then provided no way to relube, so when it wears out from lack of lubrication, that's the lifetime of the fan" - i.e. I expect you are looking at replacement.
I know nothing about your specific furnace, but I know squealing fans pretty well.