Central AC Condenser Fan Running Slow

[trader_4]

Figures when it's 92, the AC would quit. System was still
running, but the air was no longer cold. It's a Rheem, 5 ton,
4 years old. Upon checking, it seemed the fan on the outside
condenser unit was running slower than normal and the air
exiting was warmer than normal. But since I don't look at it
every day, I wasn't sure.

So, I turned it off for half an hour, then back on and went
outside immediately. The fan was running at full warp speed now,
then after about 30 secs, it went to the slower speed that
I had seen before. Luckily I had gotten out there in time to
catch it. So, clearly the fan starts up normal, the quickly
goes to running slow for some reason. Nothing is blocking/touching
it. It's also just a single stage unit, so the fan has only
I speed. I haven't
pulled out the schematic yet. Ideas? Do these typically
have a run capacitor or just a start capacitor? If so,
maybe the run cap? Or could be a bad motor. Any ideas
guys on how to diagnose? I guess they don't build them like
they used to......

[bob_villa]

I had a Rheem unit where I worked and that's how it worked normally. And 5 tons! Do you ever get the humidity out...it seems you would short-cycle and cool-down too fast?

[Uncle Monster]

On Thursday, June 11, 2015 at 7:25:59 PM UTC-5, trader_4 wrote:

You might post the model number. I could look it up to see if it has a two speed condenser fan. You could check the voltage and current draw and post your results. Look at the diagram and see if there are any sensors hooked in with a fan relay. Many condensing units have a two speed fan to help control head pressure. A low refrigerant charge or evaporator freezing up could screw with the head pressure and fool the sensors that control the condenser fan speed. o_O

[8~{} Uncle AC Monster

[trader_4]

It's a Rheem 14AJM60A01

Just looked at the documentation and it's a single speed, PSC fan,
which is what I thought it was.
It has a dual cap that works the compressor and fan. Took a look
at the schematic too and that's all there is. So, it's either
the cap or the fan motor. I don't have a multimeter capable of
testing capacitance. It looks like the caps are only ~$20 and
available on Ebay. I can probably find one locally, but IDK how
much they would charge.

Do you think the fan coming on at full speed, then going down to
1/3 or 1/4 speed could be the cap? Or more likely the motor?
Both are only 4 years old.

Thanks for the help.

[Paul Drahn]

The service people for our heat pump replaces the capacitors every two
years or so. So, just replace it.

Paul

[Stormin Mormon]

On 6/11/2015 9:52 PM, trader_4 wrote:
> Just looked at the documentation and it's a single speed, PSC fan,
> which is what I thought it was.
> It has a dual cap that works the compressor and fan. Took a look
> at the schematic too and that's all there is. So, it's either
> the cap or the fan motor. I don't have a multimeter capable of
> testing capacitance. It looks like the caps are only ~$20 and
> available on Ebay. I can probably find one locally, but IDK how
> much they would charge.
>
> Do you think the fan coming on at full speed, then going down to
> 1/3 or 1/4 speed could be the cap? Or more likely the motor?
> Both are only 4 years old.
>
> Thanks for the help.
>

I'd oil the bearings first, in case that's the issue.
ND20 or ND30 is good, two stroke gas mixing oil is
also good. Most of the time I've found caps to go bad
all at once. But for $20, go for it.

Best of luck, please let us know what you find.

-
.
Christopher A. Young
learn more about Jesus
. www.lds.org
.
.

[Uncle Monster]

You can pull the capacitor and take it by an electric motor shop or HVAC supply house to see if they'll test it for you. If you do replace it or get a service tech to repair it, insist on a capacitor rated at 440 volts AC. It's OK to go to a higher voltage rating but keep the mfd value the same. When you look at a metal can capacitor, see if the top of the can where the terminals are to see if it has bulged up. That would indicate a failure. 8-)

[8~{} Uncle Cap Monster

[Tony Hwang]

Higher value cap. is OK too when there is no exact match available.
ESR measuring adapter to go with multimeter is not that expensive.
Quite a few floating around on eBay. Cap. could be temperature sensitive
too. Good when cool, bad when hot.

[Uncle Monster]

When I was servicing HVAC systems and had to replace capacitors, I always replaced them with the 440vac rated capacitors especially in the rural areas where power surges and nearby lightning strikes were responsible for the majority of capacitor failures. Replacing the caps with higher quality and higher voltage rated capacitors usually kept those units running without failure for many years. Later, I started adding hard wired surge arresters mounted right on the condensing units and that stopped any power surge related failures of the units I installed or serviced in rural areas. Of course, there is nothing that can protect everything from a direct lightning strike. 8-)

[8~{} Uncle Cap Monster

[Wa1t 0akley]

Is that a single or two phase compressor?

[Oren]

On Thu, 11 Jun 2015 21:58:47 -0600, Tony Hwang <drag...@shaw.ca>
wrote:

>Cap. could be temperature sensitive
>too. Good when cool, bad when hot.

Does the disconnect box have fuses (2)? Perhaps one is going bad,
showing scorching...

FWIW :)
--
"We recommend using your hand to replace the fuse as it will take much longer using your knee."

[trader_4]

So, more bad news.... I thought it was a PSC fan motor from
looking at the schematics online. When I took off the cover,
the first surprise was there were only two wires on the cap
and it's hooked up to the compressor only. Upon looking at
the fan motor, it's an ECM type, so there is no cap. It gets
240V, it's supposed to do the rest.....

So, I restarted it this AM and it came up to full speed.
While it was running I had cold air. Not sure that it was
as cold as it's supposed to be, but the suction line was cold,
and it was working. So, I let it go and kept rechecking about
every 5 mins. Took about 15 or 20 mins, and then when I went
out, the fan was at the slower speed, air leaving condenser
was hotter. While
I was contemplating what to do next, the compressor kicked off,
presumably because it was getting too hot due to the fan problem.

So, now looks like I'm screwed. I haven't pulled the fan motor
yet, but looks like it's probably a $385 part. Thank you EPA.
The PSC type is ~$140. I'm thinking if I can somehow verify that
the equivalent PSC type will fit, I'd get that and mount a cap
for it. Plenty of room for the cap. Only issue is verifying that
the motor will fit/mount. Next step is take out the fan.

[Tony Hwang]

If it is not VS ECM, it must be X13 which can have speed taps. So it is
either motor itself or controller. Those motors have permanent magnets.
This type motors tend to have controller problem rather than bad motor.

[trader_4]

On Friday, June 12, 2015 at 12:10:53 PM UTC-4, trader_4 wrote:

Just before taking the motor out, I thought it might be
worthwhile to try cleaning the coils on the theory that if
they were dirty enough, it could restrict the airflow, make
the fan work harder. They didn't look bad at all, but I
cleaned them. First attempt at start-up, the fan wouldn't
go at all, then after about 10 secs, if started to spin
slower than ever. So much for that theory.....

I tried again about an hour later, and it fired right up
normal speed. Ran for about 20 mins, then went to the
slow speed again..... At least I got 20 mins of working
on the humidity/temp in the house. I think I'm going to
try it again a few times, see if I can get it to run enough
to make it more comfortable, then take the fan out tomorrow.

Best price I've seen for the fancy ECM fan is $230 and that was only
at one place, not sure they really have it. Others want
$340 - $380. The motor measures to be a frame 48 size,
can get a PSC one of those on Ebay for $50 with a cap included.
The only remaining mystery is if the mounting holes will
work. I'm guessing they will. So, I'm on the path of trying
to replace it with the simple equivalent PSC. I'm going to
open this one up on the chance that there might be some
obvious component, solder joint, etc that could be fixed.

[Uncle Monster]

I read that there is a 10 year limited warranty on the compressor and a 5 year limited warranty on the other parts. I wonder if your unit is still under warranty? Your's is the Value Series single speed condensing unit and I haven't been able to find a picture of the fan motor but I do know it has a scroll compressor. There is an ECM condenser fan motor that Rheem uses which is painted green and it may be in the "two stage" Value Series. I got on the Rheem website and found some information on your unit but I haven't found the exact parts list for your model. 8-)

http://www.rheem.com/product/air-conditioners-value-series-single-stage

The electrical specs are on page 39.

https://tinyurl.com/p2dyr7j

Catalog of the fan motors Rheem uses. The OEM motors are on page 9.

https://tinyurl.com/ossovxn

[8~{} Uncle AC Monster

[Uncle Monster]

If it's an ECM, it would be in the two stage unit. Your model number shows it to be a single speed unit. Stranger things have happened. 8-)

[8~{} Uncle Speed Monster

[trader_4]

They are using single speed ECM now to reduce energy consumption,
increase SEER, meet govt standards, etc. I think it sucks, because
of the fact that the electronics are more failure prone than a PSC,
and when it fails, it costs more. I haven't been a big fan of
ECM motors for that reason.

[trader_4]

I had found that list of Rheem motors too. Nothing on there
is apparently even ECM and the part numbers aren't even close.

The part number I found online is 51-102728-12. Found it here:

http://resource.gemaire.com/is/content/Watscocom/Gemaire/article_1374780286043_en_pl.pdf?fmt=pdf

But there is no part number on the actual motor that corresponds to
that. On the motor it says it's a Genteq 142R and also has 55ME39H
on it. Apparently Genteq is a spin off of GE's motor business.
It's just 1/3 hp, 240V, 1080 RPM

Regarding the warranty, I came to the same conclusion. It's may still be
covered under the parts warranty, but I would have to pay for labor and
any shipping. Given that I can get a new one for $230 or more likely
replace it with a more reliable PSC for $70, I don't think going the
warranty route is worth it.

I have one more hope. It seems that a common failure on these ECM
motors is the inrush current limiting thermistor that they use.
Found lots of people online where that was what it was. They burn
up, break open, etc. If I'm lucky, that might be what's gone on mine,
in which case it's a cheap fix. I'm going to open it up tomorrow.
Would have done it today, but was trying to get it to run awhile
longer to cool the house a bit.

Thanks for the help.

[Uncle Monster]

I used to replace them in CRT TV sets where they were part of the automatic degauss circuit. I wonder if you had any power surges? Do your lights blink a lot and how far are you from an electrical substation? If you have power surges, you might consider installing a small hard wired surge arrester where the power enters your condensing unit. I did it for customers in rural areas after capacitors failed too often. Square D makes a very good small hard wired surge arrester. 8-)

http://preview.tinyurl.com/pjpqh2c

[8~{} Uncle Surge Monster

[bob haller]

these OEM ONLY partss are why I bought a goodman furnace with AC.

the parts are common and affordable, generic,

[Uncle Monster]

I've sold a lot of Goodman systems but they aren't the only contractor grade systems that use generic parts. 8-)

[8~{} Uncle AC Monster

[Tony Hwang]

Isn't there anything like control circuit module or PCB with the motor?
If it is just motor, then the two leads should carry DC voltage. Back
tracing that two wires will lead to controller, I think.

[Stormin Mormon]

On 6/12/2015 11:11 PM, bob haller wrote:
>
>
> these OEM ONLY partss are why I bought a goodman furnace with AC.
>
> the parts are common and affordable, generic,
>

And, why I suggest folks not by Trane. They
use proprietary parts, can't get them else
where. Same with Sears, I've found.

[Stormin Mormon]

You may wish to tell us a couple of names?

[trader_4]

It's one of the ECM motors with the electronics built into
the end cap of the motor. It takes 240V.

[trader_4]

With higher efficiency SEER units, are you sure that still
true today? This Rheem, if it used a PSC motor, like the old
Ruud it replaced, it too would be a common motor that you can
easily find. But in the quest for higher SEER, they've gone to
ECM.

[Uncle Monster]

On Saturday, June 13, 2015 at 7:08:04 AM UTC-5, Stormin Mormon wrote:
> On 6/13/2015 12:30 AM, Uncle Monster wrote:
> > On Friday, June 12, 2015 at 10:11:05 PM UTC-5, bob haller wrote:
>
> >> these OEM ONLY partss are why I bought a goodman furnace with AC.
> >>
> >> the parts are common and affordable, generic,
> >
> > I've sold a lot of Goodman systems but they aren't the only contractor grade systems that use generic parts. 8-)
> >
> > [8~{} Uncle AC Monster
> >
>
> You may wish to tell us a couple of names?
> -

As soon as I hit "post" I was sure someone was going to say tell us. I'm trying to remember and I just did. One was "Ducane", another "Armstrong" which are two of several brands under Allied Air Enterprises. There are some other private label brands that are the same on the inside. ^_^

http://www.ducanehvac.com/

http://www.armstrongair.com/

http://www.alliedair.com/

[8~{} Uncle AC Monster

[trader_4]

I wouldn't be surprised if there are Rheem units that still use
a PSC fan, which can be multi-sourced too. And I wouldn't be
surprised if you bought a Goodman that uses an ECM motor, that
you have the same problem finding a generic replacement. Things
that were simple 20 years ago aren't so simple today.

So, update on status. I got the motor opened up. It does
have the easily identifiable thermistor, it's 1 ohm 20A.
Bad news is that it looks perfectly fine and also meters
out to 1 ohm. It's still possible that it's going partially
open when it gets hot, but I doubt it. The full motor current
is running through it and you'd think if it were partially
open, intermittent internally, it would generate heat, burn
up, be scorched, etc. That's what the pics of the failed ones
I saw online looked like.

Other bad news is that they put the electronics PC board
in the end cap, then poured 1/2" of silicone all over it,
covering up most of the components and making it impossible
to remove the board to see the backside, etc. The thermistor
sticks up above it, because it gets hot, so they left it
exposed. Theoretically, I think I could cut it off and if
lucky solder a new one onto it, but it would be tricky.
Could also put a 1 ohm
resistor in there temporarily as a test. But like I said,
given the fact that it looks perfect and measures out at 1 ohm,
I highly doubt it's the problem.

So, looks like I'm on the path to the $70 Ebay PSC motor.
Wonder if that counts as Rheem being able to use generic
parts?.....

[trader_4]

So, looks like this Fasco PSC motor on Ebay for $70 is the leading candidate:

http://www.ebay.com/itm/321759521206?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

Remaining issue will be how to mount the cap? Are there brackets
you can buy? I have room, just need some way to secure it. Guess
I can use a piece of metal plumbing strap if there isn't anything
better?

[Tony Hwang]

That electronics module can be taken out and some times it is repairable
by replacing bad component. Worth looking. If fixable, fix it and keep
it as spare. I watched Youtube once about this.

[Uncle Monster]

Did you try powering the motor by itself to see if the same problem shows up without the heat from a running system? One of the most common problems I've come across with electronic equipment is cold solder joints. If you've decided you need to replace the motor, try peeling the silicone coating off the board so you can inspect the solder joints on the circuit board. A tiny crack can cause a thermal intermittent failure which can be repaired by soldering. If you can repair the board, you can pick up a tube of high temperature silicone rubber to recoat the board. 8-)

[8~{} Uncle Circuit Monster

[Uncle Monster]

There are both single hole and two hole straps made to fit the capacitors in electrical equipment. I've also mounted the capacitor inside the control box with cable ties making sure the terminals are covered with the rubber boot made for the purpose or a heavy layer of electrical tape. ^_^

https://tinyurl.com/nmujmll

[8~{} Uncle Cap Monster

[Stormin Mormon]

Wish you would trim some trailing text.

On 6/13/2015 9:06 AM, trader_4 wrote:
> On Friday, June 12, 2015 at 11:11:05 PM UTC-4, bob haller wrote:
>> On Friday, June 12, 2015 at 11:06:40 PM UTC-4, Uncle Monster wrote:
>>> On Friday, June 12, 2015 at 7:31:23 PM UTC-5, trader_4 wrote:
>>>> On Friday, June 12, 2015 at 7:28:46 PM UTC-4, Uncle Monster wrote:
>>>>> On Thursday, June 11, 2015 at 8:52:56 PM UTC-5, trader_4 wrote:
>>>>>> On Thursday, June 11, 2015 at 8:54:22 PM UTC-4, Uncle Monster wrote:
>>>>>>> On Thursday, June 11, 2015 at 7:25:59 PM UTC-5, trader_4 wrote:
>>>>>>>> Figures when it's 92, the AC would quit. System was still
>>>>>>>> running, but the air was no longer cold. It's a Rheem, 5 ton,
||

|| [christmas presents]

[trader_4]

I can't get to the board because they put the circuit board in the
end cap of the motor and then poured 1/2"+ silicone over the top of it.
It's completely covered by it and no way to get to the backside, or
even see most of the components. I agree that it would be great if it
were accessible, because it might be a bad solder joint or there
might be some common component that you could see that was burned up.
Or it could be the IC that must be there to control it, too.

I didn't try powering it after I removed it. There didn't seem to be
much point. I agree, it's probably thermal related. In the morning
when I tried it, it ran for about 15 mins before it went to slow speed.
I let it sit for about half an hour, tried it again, and it only went
for maybe 3 mins. I did measure that thermistor and it was 1 ohm.
I took a hair dryer to it and got it too hot to touch and the resistance
dropped to about .3 ohms, so looks like it's working.

So, I'm going to order a PSC motor and the cap. I managed to locate
a bracket for the cap too. Even that was a pain, because it was
hard to figure out which bracket fits which size cap. If I'm lucky
it should all be here Tues.

Thanks for the input.

[Tony Hwang]

I think you made a right decision. ECM motor is known for poor reliability.
PSC motor will have less efficiency using more power but I don't know
how much in real life. As far as I know two most common problem with
ECM is power transistor failure in the module or winding shorts due to
heat(in this case motor won't spin free when rotated by hand) While
free spinning we can watch voltage output with O'scope for clean sine
wave.(in this case it acts like generator) I have two of them, one in my
furnace and one in the ODU. If and when either one fails, then I'll
have chance to play with it. My system came with 10 year P&L warranty.

[trader_4]

On Saturday, June 13, 2015 at 7:17:39 PM UTC-4, Tony Hwang wrote:

> >
> I think you made a right decision. ECM motor is known for poor reliability.
> PSC motor will have less efficiency using more power but I don't know
> how much in real life.

I'm betting that it's a small enough difference that I'd never
recover the increased cost.

ECM ~$240 (that's at the one place that had a price so low
I'm not sure it's real, others were ~$360+

PSC + Cap + cap bracket $85

That's a diff of $165, assuming that low price is real. I looked
at my bills recently for last summer. Looked like the AC in July/Aug
was only ~$40 a month above April/May or Sept. And that's for the
whole AC system! The condenser fan is only 1/3 hp.

I've seen online estimates that ECM saves about 20% compared
to a regular motor when they are both run the same way. The
way they get crazy low numbers for ECM is when they are able
to run it at only 1/2 speed. Like they have numbers that show
an ECM blower can be run 24/7 for low $$, but they don't tell
you that's with it running a fractional speed. If you run
any fan at fractional speed, then you do get substantial savings.

It's like a pool pump. You can get great savings by having
a 2 speed pump. You run it at half speed for twice as long,
but it saves a lot on energy because the power goes down as
the cube of speed. (I think it's cube, maybe even higher).
The 2 speed motor costs $200. Then there are pump manufacturers
selling snake oil variable speed ECM pumps, touting their great
savings. The vast majority of those savings are because they
run it at 1/2 speed or around there. Some additional savings
are because it's ECM. But the freaking things cost $1200.
You do the math. And then, what happens when the electronics
in that variable speed pump crap out, just like my experience
here? The dual speed gives you 80% of the energy savings,
it has no electronics to fail and it costs $200. Just my
2 cents.

[Uncle Monster]

On Saturday, June 13, 2015 at 5:37:31 PM UTC-5, trader_4 wrote:
>
> I can't get to the board because they put the circuit board in the
> end cap of the motor and then poured 1/2"+ silicone over the top of it.
> It's completely covered by it and no way to get to the backside, or
> even see most of the components. I agree that it would be great if it
> were accessible, because it might be a bad solder joint or there
> might be some common component that you could see that was burned up.
> Or it could be the IC that must be there to control it, too.
>
> I didn't try powering it after I removed it. There didn't seem to be
> much point. I agree, it's probably thermal related. In the morning
> when I tried it, it ran for about 15 mins before it went to slow speed.
> I let it sit for about half an hour, tried it again, and it only went
> for maybe 3 mins. I did measure that thermistor and it was 1 ohm.
> I took a hair dryer to it and got it too hot to touch and the resistance
> dropped to about .3 ohms, so looks like it's working.
>
> So, I'm going to order a PSC motor and the cap. I managed to locate
> a bracket for the cap too. Even that was a pain, because it was
> hard to figure out which bracket fits which size cap. If I'm lucky
> it should all be here Tues.
>
> Thanks for the input.

I'm curious, is it rubbery silicone or is it a hard potting compound? The rubbery stuff isn't all that hard to dig into and pick off and if you're careful you won't damage any parts but the hard stuff is impossible to easily remove. I recall some guys using a solvent to soften the hard potting compound for removal but the solvent can damage components. Anyway, most service techs never waste any time trying to repair circuit boards in HVAC equipment, they just swap it out because the labor can cost more than a new circuit board and a repaired board will not have the same warranty as a new one unless it's sent off to a factory repair depot. There was a time when there was a core charge on OEM control boards so you'd return the defective board to the distributer for it to be sent back to the manufacturer because they were interested in what was causing failures. Now there are a lot of universal replacement control boards with adapters for different cable harnesses and they're not that expensive. 8-)

[8~{} Uncle Board Monster

[Tony Hwang]

Basic ECM tester can be had for 300.00 or so.

[Tony Hwang]

That is why I always have Carrier. Getting parts is not difficult
and relatively easy to service.

[trader_4]

On Saturday, June 13, 2015 at 7:53:29 PM UTC-4, Uncle Monster wrote:

>
> I'm curious, is it rubbery silicone or is it a hard potting compound? The rubbery stuff isn't all that hard to dig into and pick off and if you're careful you won't damage any parts but the hard stuff is impossible to easily remove. I recall some guys using a solvent to soften the hard potting compound for removal but the solvent can damage components. Anyway, most service techs never waste any time trying to repair circuit boards in HVAC equipment, they just swap it out because the labor can cost more than a new circuit board and a repaired board will not have the same warranty as a new one unless it's sent off to a factory repair depot. There was a time when there was a core charge on OEM control boards so you'd return the defective board to the distributer for it to be sent back to the manufacturer because they were interested in what was causing failures. Now there are a lot of universal replacement control boards with adapters for different cable harnesses and they're not that expensive. 8-)
>
> [8~{} Uncle Board Monster

It's the softer kind, probably silicone or similar. But I think it
would be pretty hard to dig out without damaging what's there and
would take a long time. IDK what I'd even use to try. Also, I don't
know what actually holds the board in. I'm guess it was just placed
in the end of the motor cap and then the silicone stuff was put over
it. There are no screws coming out of the cap. I guess maybe I could
try to loosen it all the way around the edges and if I was real lucky,
maybe the whole thing would come out and I could then see the back of
the PC board..... Not sure I'm that determined when there is an $85
solution. Plus, even if I can expose the back of the board, no
guarantee I'll be able to find the bad part, identify it, buy a replacement,
etc.....

[Uncle Monster]

You have something to experiment with after you get your AC running. I don't know where you live but here in Birmingham there are a lot of places to get a new motor. When I was servicing AC units, I'd take the whole fan assembly by the motor shop and the guys would take it apart, cut the shaft on the new motor to length, put everything together, check the clearance and for proper operation. All the service guys did the same thing because it saved a lot of time and hassle at the customer location. Besides, stuck set screws are a lot easier to remove on a workbench where there is a vice and torch handy. ^_^

[8~{} Uncle Vice Monster

[trader_4]

I hear you. Set screw was easy..... But the fan didn't want to
come loose. So what I've done so far I did with the fan still
attached. I'm going to shoot it with PB and let it soak.

So... An update. I decided to try to get the embedded board out.
I ran an utility knife along the edges to cut it free. Then somehow,
I managed to pry it out with destroying it. The sucker was fully
embedded with the silicone stuff. Took me 15 mins to get it out.
The bad news is the back of the board is covered with the stuff.
As small amoun peeled off clean. The rest is stuck on. I did
dig out the backside by the thermistor that's a common failure.
The solder joints, one looks fine, the other, isn't perfect, but
it's probably not the problem. Still, it looked a little suspicious,
like it could be a cold solder joint. And given that the thermistor
gets real hot, I'm wondering if it's possible over time somehow
the joint went bad. So, I'm probably wasting my time, but you
got me encouraged. I'm going to reflow those two solder joints
and put it back together.

If it's not that, then I'm done. The topside is still completely
covered in silicone. And to get the rest off the backside won't
be easy either. using a knife, there is a fine line between
freeing the silicone and damaging the traces on the board. Now
if I can just find my soldering iron and solder.....

[trader_4]

On Sunday, June 14, 2015 at 12:26:21 PM UTC-4, trader_4 wrote:

So, I reflowed the solder on the two spots that I thought
didn't look quite right. Put it back together. And now
it doesn't run at all.....

So it's possible there is some loose solder joint,
partially separating component in there and my prying it
apart, etc finally made it permanently open. Or it's
possible in my process I screwed up something else on
it. Either way, it's time for the new PSC motor for sure now.....
I'll let you know how that works out.

[Uncle Monster]

This will give you an opportunity to do some experimenting with an interesting motor. You could look around on the Web to see if you can find a circuit diagram or experimental circuit board to play with and learn about ECM motors. I learned about a lot about equipment by taking it apart to see how it worked. It was a lot of fun for me and helped me understand how the things I was servicing functioned. You can find videos on YouTube from guys who cut old hermetic AC and refrigeration compressors open to show how they work. ^_^

https://www.youtube.com/watch?v=45sKWDLc4RI

[8~{} Uncle Mad Scientist Monster

[trader_4]

On Sunday, June 14, 2015 at 1:58:16 PM UTC-4, trader_4 wrote:

So, the motor got here Wed, thank you Amazon. Capacitor
should be arriving any minute. So, I started working on
getting the fan off the old motor. I'm soaking it in PB Blaster,
but so far no go. It's an aluminum collar on the fan, steel
shaft on the motor. Set screw is loose, I tried giving it
a few good blows with a hammer and punch, won't budge.
Worse, I can't drive it off, because the fan is close to
the motor, no way to get to that side. I was hoping trying
to drive it toward the motor would break it free, then maybe
I can work it back in the other direction. Puller won't
work, because there is nothing to grab onto except the fan
metal. Any ideas? I have a propane torch, but in my experience,
propane isn't hot enough to do much good.

[trader_4]

Never mind, I got it figured out. I'm going to have to cut the
shaft off. Then I can drive it out from the other side. On rain
delay right now......

[bob_villa]

Last time I couldn't get a fan off a motor...they had a set-screw on-top of another set-screw! Ouch!

[trader_4]

On Friday, June 19, 2015 at 3:40:48 PM UTC-4, trader_4 wrote:

So, the new fan and cap are in and the AC is working again!
Good bye piece of crap EMC motor, made in Mexico. Now I have
a quality PSC motor made in Thailand! LOL

Had some typical issues, getting that old fan off was the hardest
part. Still waiting for the clamp to hold the cap to show up, but
at least I have AC again. And just in time, it got hot today,
rained a few hours ago, and it's like 100% humidity outside.

[Uncle Monster]

IT'S ALIVE, IT'S ALIVE. ^_^

[8~{} Uncle Franken Monster

[trader_4]

I had it running continuously for a full hour, it's working perfectly.
Thanks again for the help.

[Uncle Monster]

Was the fan blade held on by two set screws in the same hole? Someone else mentioned running across it and it's quite common to see them locked on that way. I'd always remove the set screw in order to put Liquid Wrench in the hole and there was often another set screw under the first one I took out. ^_^

[8~{} Uncle Fan Monster

[trader_4]

No, just one screw, aluminum alloy I guess, it was all bright and shiny.
It came right out. The collar part was the problem. I sprayed it with
PB and had the same thought about spraying inside the screw hole. When
I looked inside, it was already full of PB, which makes sense, because
the shaft is flat where the screw goes, so the PB runs right in, through
the whole thing on that side, when you spray it from either end.

The problem as you know, is that there is no way to grab or drive the
fan off and it was really stuck on there. I had to cut the shaft off,
then I could put it over a steel coupling and start driving it out from the
previously inaccessible motor side. Even then, I was surprised, took
a lot of beating and I had to keep driving it back and forth each way,
spraying it with oil, until I could finally drive it all the way out.
If they put some grease or anti-seize in there it would sure help.
It was only 4 years old. I did coat it with grease this time.

[Uncle Monster]

I always rubbed a dab of antiseize compound on the shaft of fan motors I replaced and wheel bearing grease is a good substitute. Friggin wheel bearing grease has as many uses as WD-40. There is a tool I have in my collection made for pulling fan blades. Here's a link to the one I have made by Supco that's sold in any HVAC supply house. You can use the hooks or slip the tool over the hub and tighten the set screws around the bottom of the tool to hold onto the hub so you can wrench the big screw down on the puller to get blade off. Even the rental stores have them for rent. 8-)

http://preview.tinyurl.com/nf9l3l2

[8~{} Uncle Fan Monster

[trader_4]

I don't think that would work with my fan. My fan has too much
of the thin fan metal extending outward and I don't think that
puller could get around it to reach under the collar at the center.

[Uncle Monster]

I should have looked for illustrated instructions on how to use it. Here's a video that shows how to use it without the hooks. ^_^

https://www.youtube.com/watch?v=gzYpKTNchko

[8~{} Uncle Puller Monster

[trader_4]

On Saturday, June 20, 2015 at 1:13:52 PM UTC-4, Uncle Monster wrote:

> I should have looked for illustrated instructions on how to use it. Here's a video that shows how to use it without the hooks. ^_^
>
> https://www.youtube.com/watch?v=gzYpKTNchko
>
> [8~{} Uncle Puller Monster

I see what you mean. If I had one of those in my back pocket it
sure would have made the job easier. I'm kind of surprised how in
the video it pulls off the shaft instead of the puller slipping off
the collar. This one was on there really tight, but I guess that
puller thing probably would have worked.

They could also make it easier by having some threaded holes drilled
in the collar so you could grab onto using those and use a simple
plate style puller.

[Uncle Monster]

Some of the fan blade hubs have a groove around the end of the hub much like the pulley hub on some automobile alternators. It makes it a lot easier to get a standard puller on it. 8-)

[8~{} Uncle Hub Monster

[Okie...@yahoo.com]

I know I'm dragging up an old thread, but how did you wire in the psc motor. Did you have to install a contactor? If it's a heat pump how did you get the fan to shut down during defrost. I have a ecm motor doing the same as yours. Rocks back and forth but doesn't start.

[trader_4]

On Monday, June 6, 2016 at 9:35:29 PM UTC-4, Okie...@yahoo.com wrote:
> I know I'm dragging up an old thread, but how did you wire in the psc motor. Did you have to install a contactor? If it's a heat pump how did you get the fan to shut down during defrost. I have a ecm motor doing the same as yours. Rocks back and forth but doesn't start.

Wow, it's your lucky day! Usually when you re-open an old thread the
poster has moved on and you never hear back. But here I am.

First, let's make sure what you have is the same kind of ECM condenser fan
that I had. Mine had the electronics built in and just gets 240V AC power
like any conventional AC fan. Mine was powered off the contactor, so all
I did was replace what was there, wire it in the same way. I did have to
add a capacitor that connected to the new motor, but that was all. It's
not a heat pump, so I didn't have any issues with defrost. But if the ECM
fan you have now just takes 240V AC, then you should be able to just
connect it like I did. The only caveat would be that if the AC power comes
from some circuit board relay instead of the contactor, then you'd have
to make sure that relay can handle the higher current of the conventional
motor.

Out of curiousity, have you looked up the price of a new ECM? I'm
sure the PSC will be a lot less.