When blower motors go bad they start to draw more amps than they should resulting in shutdown from the control systems, or by blowing a fuse. I would check the power draw from the motor, If it is drawing more amps than is normal then it needs replaced. If it is in the right range check the power to it. If your switch and all other components are working properly I would make a best guess that the blower motor is on it's way out. That is typical of electric motors, they draw more amps when worn and will intermittenly stop working. I think you can clean and replace the brushes in them, but I don't know if you can get the parts if you are in the US. I will look for the normal AMP draw range for the motor tonight when I get home. Good luck!

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Brian W. Heitman

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