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Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 6022
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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One of my residential AC condenser fan motors won't run. The

Customer Question

One of my residential AC condenser fan motors won't run. The problems started a few days ago when we noticed the house was not cooling. I check the outside AC unit and the fan was not running, so the next day, I replaced the fan motor and the capacitor with aftermarket parts. Immediately after replaceing the parts, the system ran fine except it was running the wrong direction. I shut the system off reverse the the fan, and the motor would not start. I replace the brand new capacitor with another new one and the sytems restarted. It ran find for a few hours. I shut the system off to replace the wiring cover, and the systems would not start. Please help.
The unit is a Carrier, 11 year old.
Submitted: 1 year ago.
Category: HVAC
Customer: replied 1 year ago.
This is taking too long. How do I cancel this request?
Expert:  Phil replied 1 year ago.

Hello, it was 4 am here when you posted, most of us were asleep. It is now almost 6 am, we are starting to get up.

The life span of the condenser motor is in the 10 year range, odds are nearly 100% that your fan motor has a short in its electrical windings, nothing else will cause it to reverse directions.

To buy a new motor all you need is the Carrier unit model number, if you have that I can steer you to a place you can buy the motor.

I do not know how to cancel, I am just one of the technical experts, you can try looking for a 'report question' or 'contact us' drop down menu with 'cancel question' on it.

Let me know if you want to continue with locating a motor or not, we can go from there.


Customer: replied 1 year ago.
You didn't read my post, or it was not written well enough for you to understand my current situation. I already purchased a new motor. Most aftermarket fans are reversible. It was only running backward because of its factory settings not because it was old. Sorry for waking you up, but the system said you were "online."
Expert:  Phil replied 1 year ago.

Hello again,

Sorry for the delay, our internet connection was down for 3 hours this morning. I was able to get a few posts off early but then it died about 8:30 am... its up again now.

Do you have a dual run capacitor and are using the fan side of it to run the fan, or is it a stand alone run capacitor (cost about $7).

I do not understand your remark about it running backwards, have you reversed the rotation by rewiring it, or is it reversing itself occasionally.

If you have a dual run capacitor can you take a picture of it from about 3 feet away that shows the fan connections to the fan capacitor and some of the surrounding wiring. Use the paper clip icon at the top right end of the tool bar for that.


Customer: replied 1 year ago.
The original motor was 3 wire, the replacement motor is 4 wire. Originally I was running two capacitors, but when that setup stopped working, I converted back to three wire, by taping off the brown/white wire.Many aftermarket motors will run both clockwise and counter. You change by switching connectors.The dual run capacitor is wire blue to herm, brown to fan and yellow to common. The new motor has 4 wires. Black, white, brown and brown/white. I had to extend all wires to comfortably reach capacitor.
Expert:  Phil replied 1 year ago.

Hello again,

I will have to see a few pictures that show the motor wires and connections to the capacitor, its quite a convolution you have there. I know about reversing procedure. I owned and operated a 27 man shop that I built up from just myself working with the tools in Los Angeles California a while back.

Use the paper clip icon at the right end of the tool bar for that.


Customer: replied 1 year ago.
I just left for vacation, so I will have to send photos more photos on Monday.
Customer: replied 1 year ago.
What convoluted about my set up?
Expert:  Phil replied 1 year ago.

Hello, I am looking forward to the photo's... the various changes in wiring the two capacitors at one point would be a problem, but it depends on what you did exactly...I have to see it to sort it all out... the wire colors are not standard in all cases, referring to them alone, without a diagram to follow can lead a person off into the tall weeds.

Customer: replied 1 year ago.
The brown wire is the fan, the blue wire is the compressor, and the yellow wire is the power (connected to the white wire from the motor). These are photos I took before leaving for vacation
Expert:  Phil replied 1 year ago.

Hello again, I needed the photo's taken from 5 feet away so that I could see the capacitor wiring in context.. those are too close up, and only show the contactor connections.

I will opt out in the hope that one of our other experts here will be able to sort this out for with the information you have given.

Good luck with it.


Customer: replied 1 year ago.
Phil, your responses are disjointed. You don't seem to read what I write. I mentioned earlier that I will not be able to send you good photos until I return from vacation and theses were photos I took before I left. Yes, you should opt out and reconsider if this is the kind of help you want to provide. I will be asking for a refund.

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