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Heating, Air Conditioning, Fridge, HVAC/A/C (inside unit) fan doesn't start



My home A/C was working fine, until today. When I came in, I heard a buzzing or humming sound, and it was coming from inside the blower closet. It buzzes, but there's no starting or any mecanical movement inside the unit, no fan blowing, nothing.

The unit is a Coleman, and the temperature regulation control is a Lux programmable one, the kind that allows to program each day of the week etc.

I tried the following settings:
1) fan = on, and temp = cold
2) fan = auto, and temp = cold
3) fan = auto, and temp = off
and in all these 3 aettings I got the same result, the buzzing sound, but the fan doesn't start

The only way to get the sound to stop is when I turned the breaker off for the A/C in the main board.

Just like a side note, I've been recently remodeling some drywall, and there has been some dust around, but I have been changing the A/C filter monthly and they don't come out very dirty at all.

What could be causing the blower not to start?

Thank you in advance,


The fan motor is under stress and can't get going by itself,
motors now days are permanently lubricated but after time the bearings can still dry up.
If you can get a few drops of oil to work down the motors shaft and spin the blower wheel by hand a few times it might start on it's own for a couple of days?
When the motor buzzing starts if you can give the blower wheel a push in the rotation direction to get it moving it may go but I think in the long run you will need to replace the motor.
When the motor buzzes but won't spin a motor will shut off for a time until it cools  and then try again.
Try squirting some WD-40 down the motor shaft if you can get to it?

---------- FOLLOW-UP ----------

QUESTION: Hello Jim,

I removed the front panel. My blower unit is designed so there are 3 divided sections. The middle section has the fan and the capacitor. The upper section has the electronics card (integrated circuits), something that looks like an electro-magnet (electric wire wrapped around an iron core), and other electrical parts, and wires. The lower section is the filter, and the coils.

I got the fan spinning by hand. It's not stuck at all, and it was spinning for an amazing long time for the little push I gave to it. But when I turned the unit on, the buzz/humming sound continued, w/o the fan actually starting.

I notice that the sound comes from the section at the top, where the electric and electronic parts are, but couldn't nail down exactly which part was making the buzzing sound.

Thermostat control was set to Cool and a low temp selected, and the Fan to Auto. Then I set it to OFF, and the buzzing didn't go away! The only way the sound stops is by turning OFF the main breaker for the A/C blower in the main electric panel for the house.

Would you please give me an idea of what could be causing this? This A/C was working fine every day till this odd behavior started... Your help will be greatly appreciated.



As in my last answer:
The problem is the motor or motor capacitor, most likely the motor, the problem is not elsewhere, I'm 99% sure it's the motor, when you give the motor a push start by hand your helping it get going, it should start and run by itself but it's faulty now and can't get itself going.
you need to replace the motor or capacitor or both?

Heating, Air Conditioning, Fridge, HVAC

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Jim Barnhart


Fifty + years conditioning the air.


Answer questions about , residential and commercial. Answer questions about sheet metal fabrication. Fifty years plus experience. No answers for oil equipment, No answers for kitchen appliances, No answers for laundry appliances, I don't specialize in one particular area of the HVAC area, I'm more of a General Practitioner, Limited in refrigeration/

Hands on since 1950

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