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Anonymous Posted on May 04, 2010

RV AC blower fan turning very slowly

My RV's AC fan started acting like it was winding down when it was on, and eventually just stopped, making a humming noise. I opened up the vent and then the cover to the blower, and the blower is turning very slowly. I tried to give it a hand turning, but it was hard to turn it any faster than it was going. I'm not sure if this is the capacitor, or my blower motor. Thanks for any help you can give.

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  • Posted on May 04, 2010
Anonymous
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Joined: Feb 06, 2010
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It's the blower motor.........the bearings are seizing up when the motor is difficult to turn with power to it.
Generally, if the capacitor is bad, it won't turn at all or will quickly overheat and go out on internal overload.
If the motor feels "tight" when trying to spin it, the bearings are seizing and the motor will have to be replaced.
If there are oil ports, you might be able to spray some lubricant inside such as WD-40, but this does not always work and, if it does, it is only for a short time.....but it might get you by if you need the A/C and cannot get it repaired immediately.

I hope you find this information to be very helpful to you moving forward. :-)

Testimonial: "Thanks for the help. I'm going to have to buy another motor I suppose. Are they very hard to change out?"

  • Anonymous May 05, 2010

    The level of difficulty depends on upon your level of mechanical aptitude and abilities.

    Use Care when working with electricity. Make sure ALL power to the A/C is OFF.

    You can keep your screws seperated by using ziploc bags and marking the bags so everything goes back the same way.

    Before removing the fan blade or the mount from the old motor, take measurements of how far down the shaft the blade was located and how far from the end of the motor the mount was........this will ensure proper clearances for your new motor installation.

    Have Sandcloth and lubricant (WD-40, Liquidwrench, etc) handy......you want to sand to a shine and lubricate the shaft prior to attempting to remove the blade. Also have wire nuts, electrical tape, and wire ties handy.

    Replace the capacitor with a new capacitor. Don't use the old one.

    When you purchase your replacement motor, ask questions. The worse that can happen is the counterman will be uncooperative. The best that can happen is you can get some additional good, sound advice. :-) Good Luck in your endeavor!!!!!

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