I Have A Comfortmaker 50K BTU furnace model number GNJ050N12C1.
There is a slight rattle when the blower motor goes on. When I hold the blower motor (fasco 7021-9335) the rattle stops. I tightened the 3 nuts on the blower motor mount that attaches the motor, but that does not seem to help. What could be the problem? There are 3 rubber grommets that are attached to the bots, could they be worn? Or is it a motor problem and does the motor need any lubrication?
Thanks
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If the blower wheel is dirty, it can vibrate from being out of balance, causing the rattle you are having...