HVAC Not Running

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Our downstairs area has a Carrier heat pump system. As of yesterday, when the thermostat calls for cooling, the outside unit (fan and compressor) just buzzes. The fan does not spin, and the fan motor gets really hot. If I spin the blade with my hand, it starts running but not at full speed.
It seems to me that the starting capacitor has failed. I took the cover off to see what I could see, and the capacitor is clearly bubbled on the top. Hopefully I can find one on a Sunday to replace it.
Even with the fan running, the air is not cool. Here is the magic question. Could the fan running at lower-than-normal speed cause the unit not to cool?
This problem occurred after a thunderstorm. There were some extremely close strikes, but as far as I know, nothing else got hit, which leads me to believe that the failure was coincidental. Even if lightning got the capacitor, it's no big deal. Hopefully the compressor and controller board are still working. (I don't know how to tell if the compressor is running.)
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Yes, the job of the fan it to carry the heat away. Compressor running? Is the coil getting hot? Is the evaporator coil freezing up?

You can usually hear the compressor running. It should be starting (at least on older units) even if the fan does not run Or the lightning fried the controls.
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On 8/4/2013 7:50 AM, Ed Pawlowski wrote:

The capacitor is a GE 97F9969. It's a 7.5/45 at 370V. Both sections are open, so it's definitely bad.
Here's my next question. A friend who just had a similar failure bought a spare capacitor for his heat pump. However, it's a 5/45 instead of a 7.5/45. If I install it, and if the fan starts, is there a problem using the wrong part until I can get the correct one tomorrow? Since capacitors change value over time anyway, I suspect it will be fine for short-term use.
My primary objective is to find out whether the cap is the only problem. If lighting caused this problem, I need to determine whether anything else is damaged so I can get a service call in.
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On Sunday, August 4, 2013 10:54:40 AM UTC-4, mcp6453 wrote:

I don't know what kind of test you performed, but a cap normally appears open to DC.

I would think it would be fine for temporary use too.

I would stronbly suspect that the failure is unrelated to the lightning. The typical lightning mechanism is a surge coming in on the AC. If that happened, there is a good chance you would have seen other problems in the house. Or that the electronics in the heat pump system would have been fried, etc. The fact that the only symptom is that the fan isn't running and the cap is bulging would suggest to me that it's just normal cap failure.
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On 8/4/2013 11:12 AM, snipped-for-privacy@optonline.net wrote:

I put the new cap in, and it appears to be working. The fan started, and I'm waiting to see if it's cooling. The compressor does sound like it's running.
You can test a cap by shorting its terminals and then checking it with an ohm meter. You will see an instantaneous short circuit, but then it charges to open circuit.
Thanks for the input.
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With a swing meter VOM, that's a crude check. You're welcome.
. Christopher A. Young Learn about Jesus www.lds.org .
On 8/4/2013 12:00 PM, mcp6453 wrote:

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If you are using a digital meter, this works even better with an analog meter. Easier to see what is happening. When it's not a little cap that fills before you know it. AC caps are not little.

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On Sunday, August 4, 2013 12:00:11 PM UTC-4, mcp6453 wrote:

As you figured out that size is fine. For what it's worth, that is not a start capacitor, it's a run capacitor.
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On 8/5/2013 4:55 PM, jamesgang wrote:

come with a mounting bracket like the old one has. The electrical supplies house didn'0t have one. I secured it with a 3" cable clamp and ran a screw through the leftover tab after tightening the clamp. It seems to work great.
Anyone know where I can get a clamp? TRADEpRO TP-CAP-45/7.5/4440R MFD
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mcp6453 wrote:

Replacing with bigger cap value is OK not the other way around. If it is well secured why bother?
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On Tuesday, August 6, 2013 12:15:59 AM UTC-4, Tony Hwang wrote:

It's not a bigger cap. It's one that has a higher working voltage rating. That is OK to substitute. Replacing it with a cap that has a larger capacitance would not be OK.
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Just use some perforated strap.
. Christopher A. Young Learn about Jesus www.lds.org .
On 8/5/2013 11:34 PM, mcp6453 wrote:

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On 8/6/2013 7:35 AM, Stormin Mormon wrote:

That's essentially what the clamp did, but I thought about using perforated strap. Who sells it? Lowes?
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Lowes or HD, or auto parts places. With a hose clamp that works, I'd quit here and not go through the effort.
. Christopher A. Young Learn about Jesus www.lds.org .
On 8/6/2013 9:59 AM, mcp6453 wrote:

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On 8/6/2013 8:59 AM, mcp6453 wrote:

You'll probably find the perforated metal strapping in the plumbing department or the isle where all the metal sheet, bar stock and punched angle. ^_^
TDD
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On Tue, 06 Aug 2013 13:54:58 -0500, The Daring Dufas

That sounds right. Partially forget my previous post. (I still think it might have been a bicycle store.)
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On 8/6/2013 2:54 PM, The Daring Dufas wrote:

Yep. I found it at Lowes and fashioned a couple of nice clamps out of it. The roll will be handy to have around for other projects, too.
Thanks for the suggestion. The idea of a capacitor with 240VAC on it bouncing around inside the metal air conditioning unit is not very appealing.
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On 8/6/2013 10:50 PM, mcp6453 wrote:

Great, glad I could help. If I remember correctly, it's called plumbers tape because it's used to hang pipe and the holes make it easy for the plumber to adjust the level of the pipe. You may see it in basements or crawl spaces where the pipes are hanging from the floor joists. ^_^
TDD
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I figure that's a recipe for a short circuit, and some burnt electrical wires. Good idea to secure the cap, and make it safe.
. Christopher A. Young Learn about Jesus www.lds.org .
On 8/6/2013 11:50 PM, mcp6453 wrote:

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I just bought a roll of that last year. Cheap it was. I think it was at a bicycle store. Or if not that, Ace Hardware. Or if not that, HD.
But you don't need a clamp, just a leash. To keep it from going too far.
Or try saying to it "Stay!".
Many of them are partially trained at the factory.
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