A/C Compressor fan isn’t spinning, any ideas?

Question

Hello everyone!

I need help with my A/C unit. I started it for the first time this season and the fan on the outside unit will not spin. If I spin it with a stick, it will stay spinning but not as fast as it should be. After doing some research, I have tested that the relay works on the unit and that 240v AC is going to the motor. I am wondering if I have a bad motor or starter capacitor. And ideas on how to test these two items? Could it be something else?

Thanks!

Answer 1

put your remote to a lower setting the inside unit is set on high,. if you have done that and still not work check the contact switch relay to see if it activate

Answer 2

i would suggest the start cap for the fan may be shot. see if the cap has a noticable bulge near the top. you can check the cap by discharging and isolating it, then using a ohm meter to check for continuity. a MF meter is better, if you have one, (yeah right).

maybe you could pull the cap and have it benched checked at a friendly hvac place and procede from there. GL with it!

while i agree your cap for fan is prob the prob, i disagree with just changing it out. have it bench checked or check it yourself. some duel caps can be upwards of 50.00 bux, (from supply house for DIY's), so dont condmen it unless it's shot, OR you wind up replacing motor. if that's the case, always put in a new cap!

Answer 3

face it into the wind   LOL

Answer 4

HVAC Tech.: The fan motor could have dry bushings/bearings as these heat up they will bind and loose rpms. Most likely you only need a new start capacitor. this is because the motor will continue to run if you START it turning as the capacitor would do. When you change the capacitor you should oil the fan motor with a few drops of 20 weight oil. At each end of the motor there are oil ports with caps that can be removed with needle nose pliers..

Answer 5

Could be a faulty run capacitor, they help get the motor started.

They are cheap to replace. Replace with one of the same rating.

check the motor for any side to side play in the shaft or binding, if so the motor needs to be replaced.

Answer 6

Many hvac tech. say change your capacitor.Many of those techs don't know what capacitors do in the system.Well.here it is .Capacitors do not kick start the motor as many people think they do ,they only make the motor more efficient by raising power factor up closer to 1, rather then .7 or .8 or .9 .When a capacitor goes bad motor would not run, it is conected in searies to motor,and if u brake that bridge no power goes to motor. in your case if u have the proper voltage immediately before the motor and it does not run properly maybe motor its bad.

Answer 7

More than likely its your starter/run cap.I say this because your bearings are not stiff and the fan motor isn't smoking.To check the cap you can put it in series with a squirll cage motor for a short time(the motor will noticably speed up) Or if you have an ohm meter(de arsenvall movement) it will test short then slowly fall as it charges(ohm scale is reversed) or put a flashlight bulb in series with a battery then touch both terminals you should get a flash of light that fades as the cap charges.(caps usualy go open while resistors usualy go short in general) but easiest is to just replace it they cost about $25 or suply house will test for you(be aware they don't like DIYer's so ignore any gruffness