AC unit bad capacitor

SixPapaCharlie

SixPapaCharlie

May the force be with you
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I swear I moved from a 25 year old house that was a wood paneled cookie cutter house to a much nicer 10 year old house that certainly seemed fancy when I bought it but if I had a nickle for everything I had fixed, Well, I would take that money and use it as a down payment to get my old house back.

I come home yesterday and the kitchen is hot. Thermostat is set at 72 but shows 80. We have a small theater upstairs which is currently 95 degrees. Fortunately the other unit that is working controls the bedrooms so this is not an emergency.

I go outside and one unit is spinning just fine but the other will not spin, it is just making a buzzing noise. I had the same issue with a pool pump last year and I am pretty sure the warranty people said it is a capacitor. Same thing, I turned it on and it just made a buzzing sound.

Doc, I am looking to you. you saved me $96 with my plumbing issue.

Is this a simple thing I can repair or do I pay the $100 trip fee and have them come fix it?
 
The only really good news is I just opened a Kentucky bourbon barrel conditioned ale and I am getting less pi$$ed with every sip.
 
SixPapaCharlie said:
The only really good news is I just opened a Kentucky bourbon barrel conditioned ale
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mmmmm... want to try some of that. What brand and is it available at Midway Mart?

Be a good reason to have lunch at Mi Casita next door.
 
Simple....... probably the cap or the contactor. Disconnect the power, open it up and look. There should be a wiring diagram in there. Check the contactor, if it isn't burned up and making good contact then I would replace the capacitor. Toughest part of that is finding a new one. Make sure you get the same size...... Don't get knocked on your azz........


I have goodman, the spade terminals on the compressor would arc and destroy themselves and the post on the compressor. Had to fashion a home repair for those. I'm thinking a HVAC tech would have replaced the compressor or the whole unit.
 
I am pretty handy (read cheap bastard) so if it is a few bucks versus the trip fee, I will fix it although 220 scares me a little.

I am afraid, I will flip the breaker back on and I will go all back to the future and end up back at ACE hardware <-- not a bad callback ;)
 
Airforce one in Garland sells fan motors and Capacitors to the general public. The fan and compressor power circuits are easy. I live just across the road from you if you want to take a look at it in the morning. I have a meter to check it out. I have some experience. I have fixed mine and a couple friends. If the cap is bad, you will sometimes see them swollen or leaking a bit. Could take a screwdriver and see if the fan motor is locked up. Don't let it run like this long or you can take out the compressor.

Joe
 
Yes, capacitor. Turn off the circuit breaker for the AC unit. Remove the corner panel where the elec feeds into to the unit. Locate the big cylinder can that is the cap. Take note of all the printing off it and call: Summit Electric Supply 500 N Beach St, Fort Worth, TX 76111 (817) 831-4500. If they don't have it, try Grainger. If they don't have it, start googling.

Make note of where the wires go on the cap, take a pic if needed. Using a screwdriver, short the leads on the top to the case while holding the plastic handle. Do NOT touch the shaft when discharging the cap! Once discharged, take off the clamp, and then pull off the wires from the cap. Take it with you.

You don't need the exact Mfd measurement, but it should be close. Make sure the voltage rating is somewhat over the supply voltage. Like 290 or 370 is common. Put the wires back on the cap in the same polarity orientation as you took them off, clamp it back to the chassis and test it. If it doesn't run still, discharge the pins on top to the case, try swapping the wires on the top to change the polarity.
 
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Please be careful. Big caps are dangerous. Make DANG sure it's discharged before touching. If it has steel terminals, you might keep it safe with a magnet across the terminals.

Do not do this alone. Take the safety seriously.
 
docmirror said:
Yes, capacitor. Turn off the circuit breaker for the AC unit. Remove the corner panel where the elec feeds into to the unit. Locate the big cylinder can that is the cap. Take note of all the printing off it and call: Summit Electric Supply 500 N Beach St, Fort Worth, TX 76111 (817) 831-4500. If they don't have it, try Grainger. If they don't have it, start googling.

Make note of where the wires go on the cap, take a pic if needed. Using a screwdriver, short the leads on the top to the case while holding the plastic handle. Do NOT touch the shaft when discharging the cap! Once discharged, take off the clamp, and then pull off the wires from the cap. Take it with you.

You don't need the exact Mfd measurement, but it should be close. Make sure the voltage rating is somewhat over the supply voltage. Like 290 or 370 is common. Put the wires back on the cap in the same polarity orientation as you took them off, clamp it back to the chassis and test it. If it doesn't run still, discharge the pins on top to the case, try swapping the wires on the top to change the polarity.
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You did good until the last paragraph.

Stick with the same Mfd rating unless you have a clamp-on amp meter.

The voltage ratings for residential HVAC applications are usually 370 or 440 VAC. The capacitors must be rated higher than the Back EMF which is usually much higher than the supply voltage of 240 V. I always carry 440 V rating capacitors, as they will last longer and replace both 370/440 caps.

Wire the cap exactly like the old one and no switching wires. If it does not work, then call a service tech.

If one does not have the proper tools and knowledge, they can do more harm than good(just like flying within your limits). I get several calls a year where DIY burn components up. How much is your time worth. I have had customers go to the supply house to get a new capacitor, again for a new motor, then they finally call me. I replaced one burnt terminal.
 
let me dig up a youtube video and see the process real quick.
The above posts made it sound like a dodgy DIY project
 
Oh crap that is dead simple.
Can I buy that capacitor at Home Depot?
 
SixPapaCharlie said:
Oh crap that is dead simple.
Can I buy that capacitor at Home Depot?
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No.

Call a wholesale HVAC supplier in your area and tell them this is a cash sale. They advertise not selling to the public, but will if you ask nice. Your local furnace guy has then in stock also, and can give you good advice.
 
It is very easy...

If you know you have a visibly bad capacitor(swollen, leaking or burnt terminals).

If you have a multimeter to ensure power is off on both 120 V legs. Some techs will wire one leg straight through a disconnect to bypass a burnt lug. You pull the disconnect thinking power is off and get fried.

If nothing else is wrong, ie motor, burnt wire terminal. Occasionally a capacitor will go bad due to a bad motor. Then what? Back to the supply house or call a tech.

If you wire the correct new capacitor up just like the old one.

If I knew nothing about HVAC, I would turn off the power at disconnect and inside house at electrical panel that powers inside and outside units. Then I would check incoming high voltage at outdoor contactor. Then I would look for obvious damage or frozen fan motor bearings. Then I would get help.
 
Geico266 said:
No.

Call a wholesale HVAC supplier in your area and tell them this is a cash sale. They advertise not selling to the public, but will if you ask nice. Your local furnace guy has then in stock also, and can give you good advice.
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My usual advice...check your circuit breakers and reset, check filter, check thermostat, check units for unusual noise. Schedule me to come out. This is how I make a living. There is too many ways to get hurt if one screws up.
 
RV10flyer said:
My usual advice...check your circuit breakers and reset, check filter, check thermostat, check units for unusual noise. Schedule me to come out. This is how I make a living. There is too many ways to get hurt if one screws up.
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Here goes nothing


"Good judgment comes from experience, and a lot of that comes from bad judgment."

:)
 
SixPapaCharlie said:
Are these not them?
http://www.homedepot.com/s/ac%20run%20capacitor?NCNI-5
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Sure, that is them.

So, you order an $8 cap, have it shipped for $6 on Sep 17-19 or pick up at store for free, whenever that may be. Get home and find out you fixed it for $14 plus gas and time(whatever that is worth). That is good.

Or you have something else wrong and then can call a tech and pay $75-100 svc fee plus parts/labor. You would now already have a new cap, which usually needs replacing at 5-10 yrs anyway. That is not so good.

Or you mis-wire it and burn something else up. That is bad.

Or you electrocute yourself:yikes: and that would be really bad.
 
I just fixed mine last week. Our local lowes didn't have any. Home Depot had it online but didn't list it as being available in the store. I found a local shop that had the capacitor for $9. Amazon was selling it for $26. Took 5 minutes to change it out. I watched youtube before I did it. LOL.

There should be a box on the wall next to your AC unit. Open it up and make sure the power is off. Just remember to mark which color wire goes to which prong on the capacitor. My capacitor was bulged on the top whereas the replacement was flat.
 
I really enjoy helping my fellow pilots save money for 100LL, but would not want you to get hurt. PM for cell if you want to chat about it.
 
too late for that. I already have too much momentum. I am driving down the road with capacitor in hand jamming out to Avenged Sevenfold. get the time machine ready Doc. If Home Depot doesn't have it we'll just have to go back in time before this one failed and bring it into the future and use it.

YeeeeHaaaaaw!!!
 
You must generate the 1.21 gigawatts required to activate the flux capacitor and break the time barrier. Hopefully your fuel line does not break!
 
Go here; A-1 Electric Motor Svc Co Inc
2008 E Rosedale St
Fort Worth TX 76104
(817) 536-6145

should be in stock.
 
I went to Lowes and they did not have it. They recommended I go to A to T lamps. They certainly looked at me funny when I asked if they sold HVAC capacitors they sent me to whethertrol supply. I have a capacitor in hand I am headed home now jamming to NPR.
 
SixPapaCharlie said:
I went to Lowes and they did not have it. They recommended I go to A to T lamps. They certainly looked at me funny when I asked if they sold HVAC capacitors they sent me to whethertrol supply. I have a capacitor in hand I am headed home now jamming to NPR.
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if an idiot like me can do it, you have no excuse for messing it up. :lol:
 
He just sent me a pic of it working, so good news, he didn't electrocute himself! And we now have an extra $80 for my flight lesson Saturday! :goofy:
 
Ahhhhhhhhhh! $19.98

A cool breeze is filling the house. That means John and Martha on the big screen tonight Mrs. 6PC :)

So far POA has saved me a grand total of: $176.81 on Home repairs.
I owe POA a round of drinks.

Thanks!
 
Not to derail the thread, but i'd be screwed if my wife was on POA.. Bryan, you have big brass ones sir.
 
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