Whole House A/C stopped cooling Trane XE1000

Your life time may vary. They are cheap, so keeping one is stock to save waiting for a repairman is a good strategy.
I've heard of people stocking spare capacitors and contactors, I guess that would depend on how hot it gets where you live. When I had ants get in a contactor and gum it up it did not take long for a mail ordered one to arrive.
 
There must be another capacitor for fan there and I should get its specification so that I can pre-order it. The circuit diagram for the unit does not give values for the capacitors.
You can manually start the fan, so I wouldn't worry about it. That and the capacitor that you replaced was likely for both if it had 3 terminals on it.
 
RepairClinic says "Run Capacitor; 440v, 7.5 mfd, round" for my AC unit TTR060D100A0
Ordered it! I have no idea if it is easy to replace or not. I am sure there must be youtube video on it!

The one I replaced was 2-terminal only. RepairClinic showed 2 capacitors only. The 7.5 mfd must be for the fan.

I am hoping that I won't have to tinker with the unit for many many years.
 
That capacitor appears to have been 10 years old already when you bought it. It says "DATE: Jul 31, 2009" on it.
But it was purchased and installed in 2019. Until that time it was sitting in a box on a shelf at the store. It should NOT degrade if it is not being used.

Also to be fair, most of them have no manufacturing date or expiry date stamped on them.
 
But it was purchased and installed in 2019. Until that time it was sitting in a box on a shelf at the store. It should NOT degrade if it is not being used.

Also to be fair, most of them have no manufacturing date or expiry date stamped on them.

Capacitors can degrade when not being used. According to http://hvacrfundamentals.blogspot.com/2012/05/summer-is-capacitor-replacement-season.html :

"Any practicing service tech will tell you that service calls involving dead capacitors are common, especially in hot weather. The two most common causes of capacitor death are heat and over voltage. However, there is another less known cause: old age. Many capacitors have a shelf life. I have seen shelf lives listed as little as one year. The oxides on the metalized film break down when the capacitor is not in use, weakening the capacitor. They do tend to self-heal during use. That is why a capacitor which cannot sit on the shelf for longer than a couple of years can last for ten years in use."
 
Capacitors can degrade when not being used. According to http://hvacrfundamentals.blogspot.com/2012/05/summer-is-capacitor-replacement-season.html :

"Any practicing service tech will tell you that service calls involving dead capacitors are common, especially in hot weather. The two most common causes of capacitor death are heat and over voltage. However, there is another less known cause: old age. Many capacitors have a shelf life. I have seen shelf lives listed as little as one year. The oxides on the metalized film break down when the capacitor is not in use, weakening the capacitor. They do tend to self-heal during use. That is why a capacitor which cannot sit on the shelf for longer than a couple of years can last for ten years in use."
Good information! Then I guess it is mandatory to have manufacturing date stamped on it but from the devices I have purchased, it is NOT common to have the date on it.
 
Can I find a good link explaining why 80 mf capacitor needs to have +/- 5% accuracy? It can't be an RC tuned circuit. I bet if I throw in 100 mf there, it will work exactly like the 80 mf. But I never went to HVAC school :)

I am thinking capacitor is like a car battery capacity in Watt hours. One can always throw a bigger battery, you just don't want a lower one. Would I burn my alternator because I put a larger battery? Would my headlight blow up because of larger battery? The only penalty would be more cost and more weight in that application.
 
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You can manually start the fan, so I wouldn't worry about it.
No, you can't. The capacitors (or dual capacitor if it has 3 terminals) are run capacitors, not start capacitors. If the capacitor goes bad the motor will not run.
I have had bad luck with AC capacitors over the last 20 years. I get 3-5 years out of them. As they are cheap, I keep extras "in stock".
I also keep one for the blower (air handler) motor. They last longer because they don't get as hot as the outdoor capacitors.
 
Can I find a good link explaining why 80 mf capacitor needs to have +/- 5% accuracy? It can't be an RC tuned circuit. I bet if I throw in 100 mf there, it will work exactly like the 80 mf. But I never went to HVAC school :)
Don't do that! It can cause the motor to overheat.
 
I ordered replacement for Trane CPT01032 / CPT-1032 • 40 + 7.5 uf / Mfd GE GenTec Made In USA capacitor. It has 3 different connections marked "FAN", "C" and "HERM"; supposed to arrive day after tomorrow.

The A/C guy is coming the day after that. Hopefully, I will be able to fix it before and cancel the call.

If not, it is only $20 part. The A/C guy will probably charge me at least $200 just to show up. If it comes to that, I will ask him to install hard start kit.
Save yourself some additional future grief and order a new contactor along with the capacitor. I change both every ten years on my 22 year old unit.
 
No, you can't. The capacitors (or dual capacitor if it has 3 terminals) are run capacitors, not start capacitors. If the capacitor goes bad the motor will not run.
I have had bad luck with AC capacitors over the last 20 years. I get 3-5 years out of them. As they are cheap, I keep extras "in stock".
I also keep one for the blower (air handler) motor. They last longer because they don't get as hot as the outdoor capacitors.
If the start capacitor is bad, sure you can manually start the fan part. I have done it,
 
Can I find a good link explaining why 80 mf capacitor needs to have +/- 5% accuracy? It can't be an RC tuned circuit. I bet if I throw in 100 mf there, it will work exactly like the 80 mf. But I never went to HVAC school :)

It needs to be the correct value to create a 90 degree phase shift between the two windings. This may explain it:

 
Save yourself some additional future grief and order a new contactor along with the capacitor. I change both every ten years on my 22 year old unit.
Looks like time to get educated on contactor. It looked more intimidating when I was browsing it for fun last time.
 
It needs to be the correct value to create a 90 degree phase shift between the two windings. This may explain it:

Excellent link! I am thinking that these A/C units only have run capacitors and do not have start capacitors. The run capacitor seems to be doing the job of both. At least I did not find other replacement capacitor for the unit apart from those two run capacitors for my unit.
 
Another question. Is there a need for me to have "hard start kit" installed? When is it necessary i.e. how do I know I need it?
 
Excellent link! I am thinking that these A/C units only have run capacitors and do not have start capacitors. The run capacitor seems to be doing the job of both. At least I did not find other replacement capacitor for the unit apart from those two run capacitors for my unit.

Every A/C unit I've seen has a run capacitor. This run capacitor also functions as a start capacitor.

You can get a "hard start kit" that adds a separate start capacitor, this is normally used for compressors that have worn a bit and need a little more help starting than what the combination run/start capacitor can provide.

This "hard start kit" may also help when running the A/C unit off a generator but there are "soft starts" which are an electronic device that actually ramps up the compressor like it's controlled by a variable frequency drive, which will work better for the case where you want to run it off a generator. They reduce the start-up surge required to get the motor going and therefore you can use a smaller generator.
 
Interesting information! Looks like hard start kits are generic aka they are NOT sized for a specific compressor. That tells us that value of a start capacitor is NOT critical but the run capacitor is critical. This is dirt cheap. What are the shortcomings of retrofitting this?
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