15 replies to this topic

[ccmulder]

Seems like the fan is siezed as it sounds like the motor is trying to turn it but nothing but a hum. Any idead or thread or links on how to troubleshoot?

[jumptrout]

We need a model number.
You probably need a fan motor.
Check the capacitor first.

[ccmulder]

We need a model number.
You probably need a fan motor.
Check the capacitor first.

It is an Emerson A/C (but says "Payne" on the top of the fan)--the model# AA1CJ060-A (model number of the compressor) but cannot find any info on it. How do I check the capacitor/fan motor? I have a multi-tester. Also, there is a cable that runs to a box that looks like is has a big fuse with a handle that can be pulled out. Do I remove that or just turn the power off at the main fuse box or both?

Edited by ccmulder, 19 August 2012 - 11:59 AM.

[jb8103]

Looks like a big fuse? That's the service disconnect; pull that out to cut power to the machine. Then see if you can turn the fan blades by hand. The blades will turn in the direction that blows air out of the top. If the fan turns easily, it's probably the capacitor.

Capacitors can be sort of tested with the ohmeter but you won't get very useful data. You can inspect the capacitor and see if it's bulging on one end. If so, it's a goner.

Anyway there might still be something wrong with the fan motor.

[ccmulder]

Looks like a big fuse? That's the service disconnect; pull that out to cut power to the machine. Then see if you can turn the fan blades by hand. The blades will turn in the direction that blows air out of the top. If the fan turns easily, it's probably the capacitor.

Capacitors can be sort of tested with the ohmeter but you won't get very useful data. You can inspect the capacitor and see if it's bulging on one end. If so, it's a goner.

Anyway there might still be something wrong with the fan motor.

Well a litttle update. The fan will begin spinning if I spin it, but the air condition is not working correctly. The unit comes one--I can spin the fan to get it turning (with air blowing out the top) but the air is not cool coming out so something else is wrong. Any idea how to check if the compressor is working/not working? Could there have been some switch that shut the compressor down?

[RegUS_PatOff]

The "cold" air doesn't blow out of the outdoor unit, it should be warm.
With power disconnected, try turning the Fan Motor Shaft by hand.
Does it turn easily, smoothly ?
Can you give the Fan Blade a twirl and it will continue a few turns ?
A unit model number would be more helpful.
Does the Compressor actually run ?

[ccmulder]

The "cold" air doesn't blow out of the outdoor unit, it should be warm.
With power disconnected, try turning the Fan Motor Shaft by hand.
Does it turn easily, smoothly ?
Can you give the Fan Blade a twirl and it will continue a few turns ?
A unit model number would be more helpful.
Does the Compressor actually run ?

The fan will run fine if I turn it to get it started (it does not start on its own). And I understand the air coming out of the unit outside will not be cold, however, the air coming out the vents inside is not cool. So there is something else wrong--I provided a unit model number above. And I am not sure of the compressor is running as the fan makes a noise of course and I do not recall at this point what the sound of the compressor running sounds like.

Edited by ccmulder, 19 August 2012 - 07:44 PM.

[ccmulder]

Actually the compressor is NOT running--the only mechanical sounds are the hum of the fan motor until I start the fan then just the sound of the fan.

[jb8103]

Then my money is on the capacitor. It is a cylindrical or oblong shaped metal canister with three terminals, marked Herm, C, and F. Herm stands for hermetically sealed compressor, C for common, and F for fan. Draw a picture of the layout noting wire colors, then pull leads off. Now you must discharge the capacitor. Take any insulated handle screwdriver and short it across the Herm terminal and the C terminal, then across the F terminal and the C.

Remove the capacitor and take it with you to the supply house. There will be three ratings printed on it that will specify for them the proper replacement. It should look something like this: 5/45 380V

Install the new capacitor with power OFF. Do a good job, don't leave it dangling.

That should do it - but even if I'm wrong (heaven forfend) you're only out about $16.

[ccmulder]

Then my money is on the capacitor. It is a cylindrical or oblong shaped metal canister with three terminals, marked Herm, C, and F. Herm stands for hermetically sealed compressor, C for common, and F for fan. Draw a picture of the layout noting wire colors, then pull leads off. Now you must discharge the capacitor. Take any insulated handle screwdriver and short it across the Herm terminal and the C terminal, then across the F terminal and the C.

Remove the capacitor and take it with you to the supply house. There will be three ratings printed on it that will specify for them the proper replacement. It should look something like this: 5/45 380V

Install the new capacitor with power OFF. Do a good job, don't leave it dangling.

That should do it - but even if I'm wrong (heaven forfend) you're only out about $16.

I believe you are correct--I removed the capacitor and it is all disformed at the top (like a can that has disformed due to internal pressure. I tried testing it with my Fluke 115 which has a Farad range tester and its testing 0 so I don't know if I am doing it right or if its bad it would be 0 (zero).

Here is the capacitor: http://sphotos-b.xx....838563651_n.jpg

Here is the capacitor testing: http://sphotos-a.xx....424543568_n.jpg

[jumptrout]

The bulge on top of the cap is a sign it is bad.
With your meter set for MFD you test from C to H and C to F.
Any of these readings that are more than 15% lower than the mfd rating is a bad capacitor.
Be sure and check the wires attached to the compressor for loose or burned wires.
Loose or burned compressr wires will cause premature failure of a capacitor.

[jb8103]

Loose or burned compressor wires will cause premature failure of a capacitor.

Good info, Jumptrout.

[ccmulder]

Happy to report that after installing the new capacitor, I have air conditioning again. Just as a point of clarification as there is much confusion about this on the various sites, when you have a dual capacitor it works both the fan and the compressor (there was much confusion over the terms "start" capacitor and "run" capacitor and how a bad capacitor can effect a compressor. I saw people saying that a bad capacitor would not effect the compressor and of course they were referring to capacitor that operates the fan only. In this particular instance, the person had my exact problem but was being given bad advice initially and then much better advice later on by someone who recognized the confusion over the capacitor issues.

To reiterate--my compressor did not run at all and the fan motor made a humming sound and fan worked when spun manually--this was due to the fact that the MFDs were lower on the fan so the engine would still start but not enough juice to get the fan going. However, the compressor takes more juice so that was not starting at all and making no noise at all.

I ordered the same capacitor specifications (5/55 MFD which is the microfarad ratings for the fan and compressor, 440 Volt--as long as those two are the same, you should be fine. I was a bit concerned because all Grainger had in stock was an oval capacitor (my original was round) but the sales person fortunately was very knowledgeable and assured me it was the same thing just different shape.

Thanks for all the tips and help. Possibly this will help someone else as after doing all my research apparently these capacitor's blowing out are VERY COMMON after a change in EPA regulations changed the components that could be sued--it should be one of the first things that should be considered if fan and/or compressor outside is not working. Plus, you can pretty much tell visually if its bad just by looking at it as a bad one often completely disforms. May still be bad or going bad even if not disformed. Fortunately, I have a good Fluke multi-tester that has capacitance test capability.

As an aside, having never before tested capacitance, I was not sure I was doing it right because I got nothing but zero. So I Googled and found out you could make a capacitor out of a plastic container wrapped in tin foil filled with salt water--use a metal object in the sale water and touch one tester tip to the tin foil and one to the metal object, and sure enough it measure capacity in this quick home made capacitor. Then I knew for sure the capacitor I had was bad because it did not register anything.

[jumptrout]

Good info ccmulder..........or you could have read and done what I told you in the above narrative.
That info would have come more quickly if your problem description had been more descript.
Glad it is working for you.

[jb8103]

I'd say ccmulder kept his eyes and ears open and learned a lot. And he didn't try to get by with a cheap POS multimeter, which are often worse than useless, but got himself a Fluke 115. Outstanding.

I had a case recently with a dual capacitor that was good on the fan side and bad on the compressor side, with no deformation. Good thing I've got a Fluke, too - or I might have condemned that compressor.

[ccmulder]

I'd say ccmulder kept his eyes and ears open and learned a lot. And he didn't try to get by with a cheap POS multimeter, which are often worse than useless, but got himself a Fluke 115. Outstanding.

I had a case recently with a dual capacitor that was good on the fan side and bad on the compressor side, with no deformation. Good thing I've got a Fluke, too - or I might have condemned that compressor.

Yeah--last time I fixed something, I had my old POS multi-tester, which was fine because I only had to test for continuity. But I recalled then some other tests that might be needed if the continuity was OK (fortunately that was the problem replaced the part in the dryer and was good to go) but noted my tester could not do it or do it accurately. So I researched and bought the Fluke on E-bay at a pretty good price (forget now what I paid). But anyway my wife was annoyed saying why don't you buy that when you need it and I told her because when I actually need it, I won't have it and I'd end up going out and buying it and paying a lot more. So that was like 6 months ago and here I needed it pretty quickly. Although she got a kick out of my home made capacitor teasing me about if my multi-tester was so good why did I need to test it with tinfoil and plastic cup! LOL!!! Then, I was going around showing everyone how the new capacitor tested out just fine with my Fluke! I even used the joke, "Hey, this is no Fluke . . . oh wait--it IS A FLUKE!" LOL!!!