Hi.
Turns smooth by hand.
When energized, it acts as braking, hums and hard to turn.
There is a good chance it is wrongly wired. Resides in a condenser outside unit.
Has red, brown, black wires.
(Run) capacitor is new but may have failed.

It is this one ----> https://www.amazon.com/K48HXFPK-3958-Upgraded-Emerson-Condenser-Motor/dp/B00C6FET2M

Can you guide me for troubleshooting/diagnostics ?

 

Measure the windings to identify the pair, if they are not equal then the highest resistance one is the start (cap) winding, if the same then it can easily be reversed using a SPDT switch.

Same for 120v/240vac
Max.

 

Thank you. There is no starting capacitor. Only run capacitor. 'PSC' type of motor. No starting winding, just 'main' and 'auxiliary' windings.

 

But are the winding's identical?
It is still called a (permanent) start capacitor, hence PSC.
Someone in the Ad is still using 'Condenser'!
Max.

 

I thought that PSC is 'permanent split capacitor' as titled. Now you say it is 'permanent start capacitor' I have to learn more.

----> https://www.beckettcorp.com/support/tech-bulletins/an-introduction-to-psc-motors/\
----> https://duckduckgo.com/?q=permanent+split+capacitor+&t=canonical&ia=web

One winding is 38 ohm, the other is 90 ohm. 1/8 HP - 1050 rpm. Drives a fan.

 

I'm calling BS on the drawing Max presented. That motor is not reversible. It's a run capacitor on a permanent split capacitor motor and brown is always a capacitor lead. Only three wires? Bk is one leg of the 230VAC. Red is the other leg of 230 VAC. I believe the cap goes from red to brown. If I'm wrong, there is only one other choice: Cap goes from Bk to Brn. Always check the run current. There is absolutely zero allowance for it to exceed the nameplate rating.

 

Thanks, #12. Confirmed good capacitor, measured to specifications. This motor was for a temporary fix as the original did not start.

Dismantled the original, lubricated and found one bushing seized and spinning together with the shaft against its end cap holder. Cannot understand why a bushing is made with its exterior round allowing such. Made some notches on its exterior surface to prevent from slipping and reassembled. Unable to fit a bearing instead. Will see how long until I have to buy a new motor...

By the way, a noisy at times scroll type compressor in a heat pump exterior unit, is telling me what ? Is usually very quiet. Is it lack of condenser cooling ?

 

They have been putting such bad bushings (not bearings) into electric motors that the oil I used to use (Hoppe's Gun Oil) just bursts into flames.
Now I have to use that enamelly crap for fan motor oil.

Will see how long until I have to buy a new motor...

Very soon! Plan on buying on Monday.
One eighth of a horsie? That's the puniest fan motor I ever saw!
$170? You're looking in the wrong place!
You can buy several sizes of window air for $170!

noisy at times scroll type compressor

Any Freon leaks that let the oil leak out? Proper load of Freon in it to carry oil back to the compressor can? If not, there's nothing you can do to fix it. Of course, rinsing the dust out of the condensor fins never hurts.

 

OK, thanks. Very clean fins, zero oil leaks.
Yes, a complete window air conditioner costs the same or less than what they want for a chinese 1/8 HP fan motor.
----> https://www.amazon.com/Emerson-Tran...rd_wg=7lvXq&psc=1&refRID=MNTARKRWTD317ZS1Z2VJ

It is the institutionalized ripoff. When I grow up I want to be a CEO. Where/who do you buy parts from ?

 

Where/who do you buy parts from ?

Since my business partner died, I can't get into the HVAC wholesalers, but Appliance Parts dealers is a possibility and Grainger is usually my third choice. Get thee to the Interwebs and continue searching.

 

what they want for a chinese 1/8 HP fan motor.

About 30 years ago, I had a DC motor for a wheelchair lift rewound in a motor rewinding shop in Tampa for about $80.
12V car system, 40 amp circuit breaker, 8ga wire. Maybe 1/4 HP.
It's not going to be $80 after 30 years, but it's worth checking local motor winding shops.

 

I'm calling BS on the drawing Max presented. That motor is not reversible. It's a run capacitor on a permanent split capacitor motor and brown is always a capacitor lead. Only three wires? Bk is one leg of the 230VAC. Red is the other leg of 230 VAC. I believe the cap goes from red to brown. If I'm wrong, there is only one other choice: Cap goes from Bk to Brn. Always check the run current. There is absolutely zero allowance for it to exceed the nameplate rating.

I don't get your point?
I didn't see any more info on the motor?
Like this any better?
I was just showing the basic reversible PSC motor?
Max.

 

I thought that PSC is 'permanent split capacitor' as titled. Now you say it is 'permanent start capacitor' I have to learn more.

One winding is 38 ohm, the other is 90 ohm. 1/8 HP - 1050 rpm. Drives a fan.

The link you show use both terms for different motors.
I posted the PSC example before you posted that the motor had different windings.
That was the reason I asked.
Max.

 

I didn't see any more info on the motor?

That's because the additional information is in my head. These air conditioning fan motors were my day job for 30 years. Whatever reversible motor drawings you provide do not apply to this motor. The resistance of the windings is not equal and these motors don't have start caps at such a small size as 1/8th of a HP, only oil filled run caps. In the simplest terms, air conditioner fans are never reversed because their fan blades only work properly in one direction, therefore, any drawing of a reversible motor will not demonstrate how to wire a non-reversible motor.

I see you were quickly gathering this information while I was typing.

 

Hi Max. The schematic in your post#12 is wrong.
This is it ----> https://i.stack.imgur.com/V00xX.jpg

The original PSC motor is back into operation, started by itself, runs smooth; unit is cooling fine, with a locked bushing and extra grease given in the motor surgery; until it craps out. Tenant is happy until...

 

The original PSC motor is back into operation,

I have tried more than one McGyver trick on these fan motors and never got one to last a week after the original bearing seized up. I've saved a few bronze, sintered, oil impregnated bushings, but never a steel bushing or a steel ball bearing.
I predict bad things, soon.

 

I have tried more than one McGyver trick on these fan motors and never got one to last a week after the original bearing seized up. I've saved a few bronze, sintered, oil impregnated bushings, but never a steel bushing or a steel ball bearing.
I predict bad things, soon.

Been there done that too and for what those crooks want for a cheaply built fan motor I have machined the end bells out on several over the last number of years to refit normal ball bearings in them since by design most have almost the exact right end belll bushing cavity dimensions to fit a ball bearing into to begin with.

All the ones I have done so far needed was either a bit of reaming out plus a slot cut for a snap ring or a bushing/JB weld build up and reaming job to reduce the cavity down to fit a bearing. The blower motor in my furnace is set up for ball bearings now and that's been in there for nearing a decade and 20,000 running hours with nothing but JB well holding the bearings in place on a, 'meh, looks close enough. eyeballed in. ' fit job.

 

by design most have almost the exact right end bell bushing cavity dimensions to fit a ball bearing into to begin with.

The manufacturers arranged for some cheap steel bushings, but they haven't gotten around to revising the end plates so they can't be used for proper bearings. Give 'em time. They will get around to it.

 

These air conditioning fan motors were my day job for 30 years.

Speaking of your experience. This one's always bugged me. Mystery refrigerant losses that can be years between events. I've seen several and never had a rational explanation for them.

Units run for years then one day they are near flat on refrigerant yet have no detectable bubbling seep points or tattle tail oily residues anywhere. Recharge them expecting a leak to show up and they instead run for years more never having a problem again. Definitely not theft given their locations either. Just 'worked good last time it was used ' then near flat when started up next time.

My central air I installed about 3 years ago hit me with this last weekend. No identifiable seep points have showed up anywhere yet it only had ~20 PSI system pressure when I went to recharge it and has ran perfectly all week since.

7 - 8th one I have seen in my life that did that.

 

Have to stick up for Max here, every electric gate I ever worked on had exactly that arrangement and the same cam be said for the vast majority of small fan motors...
If you think about it why would a manufacturer fix the rotation if they didn't have to...

OK I apriciate that if you build a motor with a small euxhillarry winding and then bring out both ends it can be reversed by reversing one of the windings but that would confuse many installers.
Given the description, IE three wires, a symetrical reversible design isn't a poor suggestion, particularly for a fan!

A little harsh I thought folks....