Condenser fan motor won't start by itself

[Jaguar Fan]

On one of my AC units, the outside condenser fan motor won't start by itself. If I take a long thin stick & poke it through the top and give the fan blade a nudge, it will start.

The unit is about 8 years old.

Sooo... do I replace the fan motor? Or do I install something I've heard about called a "hard start" capacitor? Or something else?

Other units start the fan fast right away - except for one which seems to start slowly, finally building speed. Is that latter one ready to go? So do I replace the fan motor, capacitor, or add a "Hard Start"?

Thanks for any guidance.

 

[Jaguar Fan]

Here are pictures (which I should have added to my original post):

The fan motor:

Sticker on side of unit (Bryant):

Existing capacitor:

Label on existing capacitor:

 

[samss]

The 7.5 microfarad side of the capacitor is for the condenser fan motor. You can either get a separate 7.5 x 370 for the fan motor or just replace the dual cap.

 

[Jaguar Fan]

The 7.5 microfarad side of the capacitor is for the condenser fan motor. You can either get a separate 7.5 x 370 for the fan motor or just replace the dual cap.

I'm fine getting a replacement dual capacitor... I'm just wondering if it is the motor (hc39ge242) or the capacitor going bad.

Does the fact I can start it using a stick to spin the blades of the fan mean the fan motor is OK and it is probably just the capacitor that is bad?

 

[mm08822]

sound like a bad cap. If you can start the fan by turning it and it then comes up to speed it is the start cap.

Do as samss suggested. just make sure your replacement(s) are at least 370vac rated.
Open the other unit and see what size caps it has. Order a spare for it so you have it on hand.

 

[bonneyman]

The motor being made in India isn't a good sign. Heck, made in Mexico motors are better!

Capacitors used to be lifelong devices. Now - with them made in China - if you get a year or two you're lucky. The silver dimple on top of the dual cap has what looks like a wet stain around it? Could be overheated and the oil in it is pressuring out. Castor oil protected - WTH is that?

Replace the whole thing with a new dual capacitor. If the cond fan side is weak then the comp side ain't far behind. I'd opt for the AMRAD Turbo 200 multiple mic unit. Made in USA, tested to 10,000 volts, solid unit.

https://www.americanradionic.com

 

[mm08822]

measure the diameter of the cap. I got some replacements that were a smaller diameter and just made it a PIA to replace b/c the band had almost 0" take-up. Otherwise it takes longer to remove/replace cover.

 

[bonneyman]

OP, since you can get the motor to run, I'd be real interested in what the capacitance is with the system up and running. A "loaded test".

Here's the procedure. You only need a clamp meter that reads AC amps and volts.

https://www.achrnews.com/articles/135163-testing-the-run-capacitor-while-the-system-is-running

 

[machsnell]

Capacitor for sure. 10 to 15 bucks and you are back in business.

Sent from my SM-G960U using Tapatalk

 

[sms1974]

most likely a bad capacitor...

and they used to last forever when they were filled with PCB oils, when the EPA decided the PCB oils had to be banned thats when they went to ****...

 

[Wrench97]

Isn't 45/7.5 a bit of a odd size?
I seem to remember seeing 45/5 quite a bit.................

 

[Milton Shaw]

Condenser fan motors have no start winding and start switch. They get the phase change to start from a capacitor in the circuit. That is why you can start the motor by giving it a little shove. Get a new capacitor and you should be ready to go.

 

[bonneyman]

most likely a bad capacitor...

and they used to last forever when they were filled with PCB oils, when the EPA decided the PCB oils had to be banned thats when they went to ****...

Yeah the EPA only bans things that work. If the EPA doesn't like it then it's probably a good thing for the task.

 

[Jim greengo]

Yeah the EPA only bans things that work. If the EPA doesn't like it then it's probably a good thing for the task.

 

[LS6 Tommy]

No need to test anything. Replace the dual run cap. The oil stain on the top of the cap tells me it's shot.

Tommy

 

[firebirdparts]

That is an odd size, but I bet there is a factory where they will churn you one out.

 

[bonneyman]

That is an odd size, but I bet there is a factory where they will churn you one out.

Yeah, a 4 ton with a 45 mic cap. Hmm.
Usually scroll compressors have caps with high mic ratings (70-80) compared to older recip compressors (35-55). I think (big wink wink here) it has to do with scrolls use less current to run (to save energy) but thus require more MFD's to develop the needed torque.
So this big a compressor (with a TXV no less) running a 45 mic cap seems a bit odd.