SIGforum
Preferred brand for AC motor run capacitor?
May 27, 2025, 11:59 AM
trapper189Preferred brand for AC motor run capacitor?
quote:
Originally posted by konata88:
I replaced one cap recently but it's made in chicom. i will buy an amrad spare.
there is another cap at the blower. it's 15uf +6 - -6%. Can i replace it w/ this one from amrad:
https://www.amazon.com/AMRAD-E...TW/ref=sr_1_2?sr=8-2The current one is something like this:
https://www.amazon.com/Capacit...TW/ref=sr_1_1?sr=8-1The specs are a little different but close enough? Or do i need to find an exact match?
You don’t want to use a round cap in an oval mount or vice versa.
Looks like USA2034 would work.
May 27, 2025, 12:02 PM
ZSMICHAELThey call that price gouging here. After a particularly bad hurricane it is against the law to raise prices.
Before that happened all kinds of price gouging went on. I remember the local Otasco store selling chain saws and other supplies for triple the usual price. Word got around and they were out of business within a year.
I would never do business with an AC firm like that. Do you realize that he thinks you are stupid?
May 27, 2025, 12:15 PM
konata88quote:
Originally posted by trapper189:
You don’t want to use a round cap in an oval mount or vice versa.
Looks like USA2034 would work.
Thanks! I can't find a USA2034, including on AMRAD website. They don't seem to offer an oval can 15uf capacitor.
https://amradmanufacturing.com...otor-run-capacitors/Would the specs on the USA2209 work for me?
Is there a functional concern with a round vs oval can? Or just mechanical stability in the mount?
"Wrong does not cease to be wrong because the majority share in it." L.Tolstoy
"A government is just a body of people, usually, notably, ungoverned." Shepherd Book May 27, 2025, 12:16 PM
TomVquote:
Originally posted by RogueJSK:
Everyone should have a spare capacitor on hand, since it's the most common reason for A/C failures, and it's something that just about anyone with an ounce of DIY ability and access to Youtube can swap themselves.............
Can I order a spare just knowing the make, model & serial number of the AC Unit ?
Or do I need to pull the cover and CAREFULLY look at the existing Capacitor ?
Thank you.
May 27, 2025, 01:00 PM
sigmonkeyTypically, the manufacture data plate/sheet does not provide the value for capacitors.
There are some sites that you can search that have the correct values for capacitors for quite a few units, but it takes some digging.
Identified by compressor make/model, as well as fan make/model.
You need to check the one you have, but realize some techs will stick what they have on their truck to clear the ticket. (shameful as that is).
If you find a good HVAC tech that is trustworthy, get their name and request they do your service, or call them directly if they have moved on to another company.
"the meaning of life, is to give life meaning" ✡ Ani Yehudi אני יהודי Le'olam lo shuv לעולם לא שוב! May 27, 2025, 01:02 PM
Puckpilot78[/QUOTE]Can I order a spare just knowing the make, model & serial number of the AC Unit ?
Or do I need to pull the cover and CAREFULLY look at the existing Capacitor ?
Thank you.[/QUOTE]
I’d do both, never know if someone threw in a different one in a pinch.
I’ve used Capcom brand ones in the past, “assembled” in Mexico. Can’t say I’ve had any issues.
Mongo only pawn in game of life... May 27, 2025, 01:17 PM
trapper189quote:
Originally posted by konata88:
Thanks! I can't find a USA2034, including on AMRAD website. They don't seem to offer an oval can 15uf capacitor.
https://amradmanufacturing.com...otor-run-capacitors/Would the specs on the USA2209 work for me?
Is there a functional concern with a round vs oval can? Or just mechanical stability in the mount?
It’s mechanical stability. I tried an oval one once because it’s what they had in stock. I rigged that seemed sturdy enough at the time, but 4 months later it slipped and shorted against the mounting strap. Fortunately, no permanent damage.
As far as specs, you have to use the correct capacitance, the uf rating. I once read why and it made sense at the time, but I cannot remember much. Something about the motor’s windings, phase something, rotational magnetic field, I don’t know. Whatever it was, it wasn’t a case where a bigger one could be substituted.
The VAC is a different story. You can use a cap rated for 440VAC instead of one rated for 370VAC, but not the other way around.
I don’t know about the tolerances. I suspect the difference between +10% -5% and +6% -6% wouldn’t matter.
I would get whatever USA made brand I could.
I’ve never needed to replace a cap for the blower motor. I have done at least 5 for compressors, 2 contactors, and 1 breaker.
May 27, 2025, 01:33 PM
sigmonkeyquote:
440VAC instead of one rated for 370VAC
Yes, and that provides better margin of reliability as the higher 440V rating cap can withstand any surge in voltage without damage (in a lower voltage system), but the microfarad rating has to be the same.
"the meaning of life, is to give life meaning" ✡ Ani Yehudi אני יהודי Le'olam lo shuv לעולם לא שוב! May 27, 2025, 01:47 PM
selogicquote:
Originally posted by Russ59:
quote:
Originally posted by HRK:
at VT said, iF you've ever spent an hour on your knees replacing a capacitor in the middle of July when it's muggy, humid, no air circulation and 98 degrees, $200 is cheap,
$565 isn't a good price considering the guy was at the house already, it should have been the cost of the capacitor and labor.
This should take 10 minutes tops. It while take longer to walk back and forth to flip the breaker.
Thanks all.
I believe code requires a disconnect switch at the AC unit outside .
May 27, 2025, 01:58 PM
stoic-onequote:
Originally posted by selogic:
I believe code requires a disconnect switch at the AC unit outside .
Older houses may or may not have a local disconnect, certainly modern construction will have a non-fused disconnect within sight of the unit.
May 27, 2025, 03:24 PM
TomVquote:
Originally posted by Puckpilot78:
quote:
Can I order a spare just knowing the make, model & serial number of the AC Unit ?
Or do I need to pull the cover and CAREFULLY look at the existing Capacitor ?
Thank you.
I’d do both, never know if someone threw in a different one in a pinch.
I’ve used Capcom brand ones in the past, “assembled” in Mexico. Can’t say I’ve had any issues.
So I pulled the cover a took pictures of the Capacitor.
Looking on the AmRad website they list one of the correct size (75/5) and it is close in physical size (height is within 1/2"), part number USA2222B.
I can't find any manual for the unit a Tempstar (Carrier) N4A360AKN400.
The house is about 4 years old, but I don't know if the previous owner ever had work done. So I'll ASSUME that the Capacitor that is installed is the correct size.
Thanks again.
May 27, 2025, 03:38 PM
sigmonkeyquote:
N4A360AKN400
Yes, Tempstar shows it as 440V 75+5
"the meaning of life, is to give life meaning" ✡ Ani Yehudi אני יהודי Le'olam lo shuv לעולם לא שוב! May 27, 2025, 04:29 PM
konata88quote:
Originally posted by trapper189:
quote:
Originally posted by konata88:
Thanks! I can't find a USA2034, including on AMRAD website. They don't seem to offer an oval can 15uf capacitor.
https://amradmanufacturing.com...otor-run-capacitors/Would the specs on the USA2209 work for me?
Is there a functional concern with a round vs oval can? Or just mechanical stability in the mount?
It’s mechanical stability. I tried an oval one once because it’s what they had in stock. I rigged that seemed sturdy enough at the time, but 4 months later it slipped and shorted against the mounting strap. Fortunately, no permanent damage.
As far as specs, you have to use the correct capacitance, the uf rating. I once read why and it made sense at the time, but I cannot remember much. Something about the motor’s windings, phase something, rotational magnetic field, I don’t know. Whatever it was, it wasn’t a case where a bigger one could be substituted.
The VAC is a different story. You can use a cap rated for 440VAC instead of one rated for 370VAC, but not the other way around.
I don’t know about the tolerances. I suspect the difference between +10% -5% and +6% -6% wouldn’t matter.
I would get whatever USA made brand I could.
I’ve never needed to replace a cap for the blower motor. I have done at least 5 for compressors, 2 contactors, and 1 breaker.
Thanks!! Good info to know. Very helpful.
I have replaced both caps under duress (ie - it was during the high heat of summer) so it was cheap parts. I think the condenser twice and the blower once over the past 25 years. I aim to be ready with amrad parts the next time.

"Wrong does not cease to be wrong because the majority share in it." L.Tolstoy
"A government is just a body of people, usually, notably, ungoverned." Shepherd Book