Do I have an HVAC issue or an electrical issue ?

EddieZoom

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Central air conditioning installed ~20 years ago. On my second condenser. In the past, we have occasionally had issues with the 20AMP breaker tripping for the condenser....not a huge deal. During our recent multiple heat waves this year, we are tripping that breaker 8-10 times some days....others 3-4 but can't run an entire day (it rarely, if ever shuts off due to crazy heat). Tried to correlate the trips with some other hi draw appliance...but "data is inconclusive" as they say.

Other than change the A/C filter on regular intervals I must confess we do nothing to maintain/PM the system....hasn't been an issue till now.

I'm likely going to limp along until the weather breaks.....but what am I likely looking at here...HVAC or electrical ?
 
(not a lawyer)
I'm going to guess electrical within the HVAC.
I've gone through 2 contactors in 12 years at my house.
Clean up / replace the contactor / wires / connections and I bet it will run better.
oh yea, and capacitors go bad in these things even more than contactors.
( I know nothing about electricity besides it can hurt you)
Amazon product ASIN B0195UUDAM
View: https://www.amazon.com/Carrier-Replacement-Condenser-Contactor-HN51KC024/dp/B0195UUDAM/ref=asc_df_B0195UUDAM?tag=bngsmtphsnus-20&linkCode=df0&hvadid=80608063550961&hvnetw=s&hvqmt=e&hvbmt=be&hvdev=c&hvlocint=&hvlocphy=&hvtargid=pla-4584207590256788&psc=1
 
look at the starter capacitor, see if it is bulged...as in no longer round because it has failed inside

If the starter cap is gone the motor will struggle to start, and normally cut out before it can start.

Usually it resets at the unit, but if the breaker in the house is a tad off it might be popping the breaker before the thermal or over current device in the unit
 
My 20+ Carrier AC worked for a week in June then failed, three weeks before the big heat wave. I saw mice damage patched it but didn't fix the problem. The capacitor was mounted upside down so I missed the bulging, very obvious if u watch a YouTube video
 
the tonnage of the unit and the FLA, full load amps, is going to determine the breaker size, as well as the size of the conductors going to the unit from the panel.
have an electrician look at it, it's probably an undersized breaker, fed with undersized conductors
 
Could be a bad start cap.
Could be low on refrigerant and there is icing
Could be a clogged condenser coil
Could be a clogged evaporator coil
could be a clogged return air filter
could be a bad txv
could be mice eating wires
could be a bad heater element if its a heat pump compressor
ect....

check filters, check for a clogged condenser coil, call a pro.
 
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Thanks everyone. I'll do a little more troubleshooting with the advice given and then likely make some calls and get on a waiting list.

Fortunate that I can limp along until Fall shows up without too much hassle....better than down/down.
 
We had some mystery outages when we first started running a window AC in our house.

Turned out, when running the AC, and some other things, it would kick out once in a while. Finally figured out the dehumidifier downstairs was on the same circuit, and when that randomly kicked on, it was enough to blow the fuse. Moved that to a direct line in basement, not off the sub-panel (older fuse box); problem solved.
 
Could be a bad start cap.
Could be low on refrigerant and there is icing
Could be a clogged condenser coil
Could be a clogged evaporator coil
could be a clogged return air filter
could be a bad txv
could be mice eating wires
could be a bad heater element if its a heat pump compressor
ect....

check filters, check for a clogged condenser coil, call a pro.
Probably start with a meter to see what’s broke first. 😆

I just cleaned my evaporator coil last week. Pushed the brush thru the trap and have it a visual once over.

PM is very cheap. Not being uncomfortable is priceless.
 
Always test your capacitor when this type of issue arises. Use a multimeter with an ohm tester. Just be sure to short the capacitor before messing with it. Take a screwdriver and touch both contacts. These are like $20 parts and easy to DIY.
 
here's an odd problem i had about 3 years into my new house with the a/c breaker blowing. called an electrician, he checked a bunch of things, then pulled the meter and found corrosion on the contacts. cleaned it up, no-ox grease on the contacts, never had another issue and ran great for another 27 years. at that point when the cap went it was over-due for a new condensor anyway
 
Don't breakers start to get "weaker " the more times they are tripped?
I'm sure there might be more to it, but I'd replace the breaker anyways
 
Licensed electrician here. I’ve wired condenser’s that range from 20A-50A. The size of the unit is determined by how many BTU’s is needed, with each requiring their own specific amperage. Just upgrading the breaker to a higher amperage could cause an immediate fire if the wire isn’t rated for that breaker.

Palladin and Mr. Brownstone’s comments are 100% correct and necessary for us to move on to your next step.
 
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Could be a problem with either or both. A whole list of possibilities come to mind but I wont guess from behind a keyboard. The breaker is telling you there's a problem. Flipping it back ON all the time and you may come home and find a smoldering heap where your house once stood.. Get it checked by a professional.
 
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like @appraiser says, startup cap is obvious culprit to begin with.
These guys are most likely right.
Also, as they get older they draw more starting amps and a hard start kit can be added to aid in this.
Easy to do.
A capacitor and a hard start kit shouldn’t be more than 50 bucks diy.
 
You mean when the contacts make the 30, 40 or 50 amp connection it arcs a little?? 😂
No, I meant when it trips out randomly for no good reason, turning out to be an actual reason. Mine was with window units AC, not whole house. Just throwing the monkey wrench for what could be wrong at it.
 
Post a pic of name plate. It will list min circuit ampacity and max breaker size.

When it’s running, how does it sound? Could be the fan cap or the fan itself, those are relatively cheap/easy fixes!
 
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