Condenser Fan stops running- Fan or capacitor?

[Guest horn4life]

Goodman CKJ48-1AB

Thought that AC wasn't cooling 100%, and low and behold went outside and condenser fan was not turning and fan was hot as well as entire unit. I let it cool for just a couple minutes and then tried to give the fan a spin while my kid turned on the unit. Fan spun fine for a few minutes, the crapped out. I was unsure if perhaps having the fan unit so hot might have been part of the problem and causing the fan to shut down.

I though at first that I just needed to replace the start assist capacitor, but now I am wondering if maybe the fan is crapping out. It turns fairly easily, but seemed to come to a stop abruptly. Not grinding or hard to turn, but maybe not 100 percent?

So is there an easy way to test to see if the fan motor needs replacement? not an electrical genius but pretty handy. Already read about discharging the capacitor for safety.

thanks in advance

[RegUS_PatOff]

with power removed, try turning the Motor shaft by hand..using your fingers...

Does it turn easily, smoothly ?

Can you give it a twist, and it will continue for a few turns ?

If replacing the Motor, you should also replace the Capacitor,

(at least the Capacitor section for the Fan)

[Cactus Bob]

if the cap is bad the motor will not start on it's own at all ,

if the cap is bad you can give the motor a spin backwards , turn on power , motor will run backwards , it will be weak but will still take off backwards

the motor cap you have in your unit is not a start cap , it's a run cap

the way you said that the motor ran and then stopped quickly tells me a bushing / bearing problem , not a bad capacitor problem

[Guest horn4life]

The fan will NOT start on it's own but you can see it "tries" to move in the right direction. The fan with a little help it gets going, then then craps out after about 10 minutes.

The fan motor will NOT run backwards at start with a reverse assist.

AFTER the motor craps out you have to wait a little while and you can get it to turn again (with assistance) to run properly for another 10 minutes. I don't want the compressor to overwork so I have been standing next to it waiting for it to die, then run in and shut down the unit down.

Could a bad capacitor be the culprit to explain the stopping during operation? OR is it more likely a problem with the motor?

When the motor craps out it doesn't make a noise or come to a grinding halt it just stops.

[RegUS_PatOff]

... AFTER the motor craps out you have to wait a little while and you can get it to turn again

seems like the Motor is over-heating.

When it stops, feel the Motor to see if it's hot.

with power removed, try turning the Motor shaft by hand..using your fingers...

Does it turn easily, smoothly ?

Can you give it a twist, and it will continue for a few turns ?

If replacing the Motor, you should also replace the Capacitor,

(at least the Capacitor section for the Fan)

[Cactus Bob]

The capacitor is fine

the motor is bad

100 %

[Guest horn4life]

-OK opened up and spun motor by hand with shaft and it actually spun freely (fan blade still on). I was expecting it to not turn as freely...

-Motor is definitely hot when motor shuts down. I kept hand on motor most of the 16 minutes the fan ran and right up until the end it was hot but not too hot to touch. About the time it got really hot the motor shut down..

-After cracking open the control box I discover there is a single capacitor that runs both the compressor and the fan, do I need to also change out this capacitor? Or should I just replace fan and see what happens? I don't mind paying for both the capacitor and the fan motor, but of course do not want to spend more than necessary.

ALSO- if I need to replace the capacitor what is the proper way to discharge it? three post C, F and HERM.

Thanks in advance for your input- sourcing parts now...

Edited October 5, 2012 by horn4life

[RegUS_PatOff]

that's a dual Capacitor .. two sections .. one for Fan, one for Compressor

Could be about $ 50

OR just a replacement for the (smaller section) Fan Capacitor .. about $ 5

If replacing the Fan Motor, install a new Capacitor (matched to the rating needed for the new Motor)

C = common

F = Fan

HERM = (hermetically sealed) Compressor

I'm not a HVAC master, but if the run Capacitor was bad (or nearly 0 MFD)

might the Motor run, but then over-heat after a few minutes ?

OR not over-heat at all ?

[Cactus Bob]

the motor may spin by hand no problem ,even if the motor is bad

your replacement motor most likely will be a universal motor that will use it's own cap , that will be a 5 mfd to a 7.5 mfd . if you go with a oem motor it will connect to the cap already there

you do not need to discharge this cap , it's mfd's are to low to be of any danger , but be aware if you have a black plastic cap in there too (compressor start cap) you will need to discharge that one before you stick your hand in there

regus: newer caps do not get weak , its a good or bad with them , really old caps can dry out and get weak but this is not the case in this case . a really weak cap might start the motor and overheat it , but a bad cap will never be able to give the motor direction (the cap makes a phase shift in the delta type windings this gives the motor direction )

again i go back to the way the motor stops and a clue to the motors health , and it's not good

[Guest horn4life]

Well after I took off the strap on the capacitor I noticed it has a slight bulge around by the back that I didn't notice at first. Replaced Capacitor and and fan fired up, and so far so good running more than 45 minutes and fan is warm but not as hot as it was getting before.

THANK YOU ALL for your input! Got lucky and looks like the cheapie fix was the right fix. Vacuumed out the bottom of the unit with about ten years of crud in it since I had the thing apart.

[Cactus Bob]

well , nothing like being wrong , glad you got it fixed

it's hard to get some of these things right sometimes going only by words typed on a page

what is free spinning to you might be tight to me or the other way around

it is rare for a cap to go bad half way

so i stand corrected

[jb8103]

That's a new one on me, too - a bad cap causing an overheat condition...I dunno, I think there might be a bit more to this one. Anyway, into the bag of tricks, although I always test them anyway.

[Shootist]

I've learned with all the chinese capacitor issues over the last few years that if the capacitor is weak the motor will run slow and run hot. I check the uF on the cap with my meter first thing. If you don't have a meter they aren't all that expensive. I've bought nothing but Amrad caps for 3 years now.

[JTyler]

My AC condenser originally had a fan problem.  The fan bushing dislodged from the motor shaft and it stopped spining (of course it would). Loacal AC guy came out for $89.00 and told me I needed a host of things...new fan (special order), new motor, new start/run capacitor....new type of freon...$1,150.00!  I told him to get lost because I can get a new fan for $20.00 and a motor for about $150.00 so his labor isn't worth $980.00.  I then went online and bought a new fan for $22.00 and installed it.  AC ran fin all Summer of 2018.  It is now August 19th.  A couple days ago the fan stopped while I was out in my pool next to it.  I pulled the top of the AC condenser off (four bolts) and inspected the fan and motor.  Fan is still intact.  The motor was hotter than you know where!  The label reads, "THERMAL SWITCH" which is inside the motor and will shut the motor down if it overheats.  It overheats due to a very faulty cap or a faulty motor.  My unit is 22 years old!  So, I ordered a new motor and cap.  DO NOT BUY A START/RUN CAPACITOR THAT EXCEEDS THE NUMBER OF MICRO-FARADS LISTED ON THE EXISTING CAPACITOR.  I say that because mine is  30 UF +0.3 cap and I bought a 50+ UF cap at 470 volts.  I installed that cap and the motor shut down in five minutes. So, I read on Google what I highlighted for you, and ordered a 30+ UF cap.  Meanwhile, I installed the old cap and the motor was cooled.  The AC ran for about 1.5 hours and then shut down the fan due to overheating.

My new cap and motor arrive Wednesday, so I'll change them both out.  The motor cost me $165.00 from Amazon, and the cap came from another supplier.....so $180.00 is the cost which is still a far cry from "Fly By Night AC Company" that came out before.  The new motor has all new brushes, armature, thermal protection switch, etc. so everything will be fine.

John Tyler - Monroe, NC

[CrazySaguaro]

Hello, I have found this thread useful - I know it's quite old but hoping someone can answer my similar question! 

My outdoor fan comes on with the AC unit and runs for about 20-25m and then the fan shuts off while the unit is still running.  It's free turning when I turn it with a screwdriver (not bound).  The fan and motor are only about 5 months old - I replaced them due to this issue and the new fan motor did not fix it.  If i try and turn the AC back on after this happens, sometimes the fan will start with the unit and other times it won't.  If I wait until way later (hours), the fan will start with the unit and run another 20-25m before turning off (while the unit is still running).

Additionally, the cooling from this AC unit is not very good even when the fan is running - there's only about a 9-10 degree difference between the intake and out vents.  So it seems to cool very slowly.

Any advice, please let me know!

Thank you,

Gina

[Drew55]

Gina I’m having the exact same problem.  I replaced the motor and the capacitor and neither fixed the problem.  I’m at a loss.  Any help would be great! 

[Rosskious]

Straight AC or HeatPump? What is your Model number? 

[Pwood]

New to this site however have an issue similar to above. AC unit (old) has been running fine until couple days ago. Its comes on, may run for 15-20 minutes then fan stops & unit makes loud noise. Its hot. In looking at the posts it seems like folks are being pointed in direction of capacitor or fan motor. I am semi handy-don't have an ohm meter (couldn't read it if I did) however some of these comments about the electrical are scary. Any suggestions?

 

[Rosskious]

Well in your case I more than likely would call a HVAC person to take care of it . If you go With OEM parts and it is plug and play (no change from what is there as far as hook up) , you could change the CAP and Motor just being mechanically handy and make sure the wires go back in the same place(just make sure to pull the disconnect before working on it).

[Lost00Clown]

Same or similar situation.   Trane xb1000

Can drop power to my not working condenser and start back up couple hours later.   Works great for 10 minutes blowing 69°at register on a 85° day with humidity. 

One copper line cold and one warmer like normal.  The fan stops on the condenser.  Compressor still running.   

 

Replaced capacitor because it was cheap and could get next day.   Still same, fan on condenser stops after a few.   Took the temp at fan motor and it was over 200°.  Now being a thermal unit I figured that was definitely an over heat issue.   

Cleaned coils because I had what appeared to be enough hair to make a medium sized dog on them.  Tried again after washing out well. Same. 

Fan motor free spinning but shuts down about 200°

Did find a lose red wire on the contactor. Crimped for better connection.  Still same issue.   

Ordered a new contactor, again, cheap.  Figured I'd revamp all the cheap parts.  Easy enough to do anyway.  

 

Think this could be the fan motor itself?  Anything else make it shut down like that?

Background, been working fine for years.  Did have a heavy storm.   

[Cactus Bob]

Your motor is bad. replace with OEM motor if you can afford it and can still get it .

[Renew]

Hi, my ac fan seems to be over heating and shutting down. It starts by it self, and cools. Sometimes it will stay on longer than other times. Is it possible that this issue could be caused by the capacitor? Or more likely the fan motor? Filter, and coils clean; vents are open. thank you

[Chris Reynolds]

My AC suddenly started having the same issues mentioned in this thread. After running fine for like an hour the condenser unit fan would stop but the compressor would continue working. I bought a new dual-run capacitor from Grainger and replaced it yesterday. AC started back up, and it repeated the same issue. Fan stopped after an hour, and it's really hot to the touch. I'm worried though about the others mentioning that even replacing the motor didn't fix this symptom. Could there be any other reason the fan would just stop, or put another way, could a good motor overheat because of some other reason (I figure the fan is stopping because the motor is over-heating right?)

I think I'll try checking the ohm load on the motor. Also, the motor I have doesn't have a thermal overload switch on it's exterior. Not sure if it's external or if it even has one. Any thoughts or suggestions would be most appreciated. 

Here is a link to my drive folder share that has pics of the motor, old capacitor (new one is a Titan with the same specs from Grainger), and the schematic and model info/spec sheet

https://drive.google.com/open?id=1grZ8eUWjByFol_cpuomImiekyLdhT4JD

Thanks,

Chris

[Budget Appliance Repair]

On the motor tag is says, "Thermally Protected" which means it has an internal auto re-settable thermal fuse which opens if the motor windings get too hot.

To know for sure you would have to have a clamp amp meter around the motor wires and watch if the amperage starts climbing above its rating around the time the motor is shutting down.

[Dangtoohot]

Ok so I had same issues listed above pulled motor and capacitor out of a running exact same unit put in mine and now compressor kicks on contractor working as it should and still condensing fan will not run and all parts are oem and brand new off running unit makes absolutely no sense please help my house is heating up hotter than outside temperatures in the day time and it’s 3 am and finally down to78 degrees