Air conditioner Trips Circuit Breaker-Call Electrician or A/C guy?

I have a 4 year old Lennox central air conditioner. It has run fine until this summer. Now after it has been running for about 15 minutes the circuit breaker trips and the outside condensor fan stops. When running it does blow cool air.

I have heard that it could be the compressor or something else with the A/C unit or it could be a bad breaker. Since the unit is only 4 years old I am thinking that it is unlikely that the compressor has gone bad. If it were a bad breaker wouldn't it trip as soon as the unit turned on? Any thoughts?

Reply to
ewingil
Loading thread data ...

While it could be either, I'd call the AC guy. The electrician will say "yep, overloaded, pay me $75 and call the AC guy" but the AC guy can determine why it is tripping the breaker and fix it.

Reply to
Edwin Pawlowski

Was this a new or replacement A/C system?

If it was a replacement, I would tend to go with the idea that they may have used the existing breaker and it may be rated marginally for that unit. You need to check the recommended protection for that specific unit or it may just be tired and need replacement. That one you can do yourself IF you are reasonable competent and careful. But you will need to know what the new system calls for and if it is larger, you might also need to replace some wiring.

On the other hand if it was not a replacement, I would tend to suspect the compressor.

The electrician is not going to be qualified to check the A/C, but the HVAC contractor should be able to determine that the A/C is OK and that the correctly rated breaker is in use.

Reply to
Joseph Meehan

It is a replacement and they did use the same breaker. If it were a marginally rated breaker wouldn't it have started giving trouble before this? Thanks for your input.

At any rate, I have called the A/C company > snipped-for-privacy@yahoo.com wrote:

Reply to
ewingil

Neighbors had a similar problem -- breaker for central A/C kept tripping. I replaced the breaker with a brand new one of the same rating and the problem went away.

Reply to
Howard Beale

Yeah, that's what I was going to do too, but two electricians told me that it was more likely to be an A/C problem

Reply to
ewingil

New ac unit can be shall we say tight. have higher FLA (full load amps) to start with then after some use. an older breaker that has tripped a few times is the same way it trips at a lower current than it did when brand new, were talking 10ths of an amp if that. loose wires on the breaker will also cause tripping, seen that on our AC unit, check the wires make sure they are very good and tight. Ours would work fine for a while then when system had to work harder due to outside temp, and longer running cycle would trip out, was only loose wires.

Reply to
Jeff

Why not do that first? If it doesn't work, you're out $10 and the 10 minutes it takes to replace a circuit breaker.

If it does work, you've saved a pile of money and the aggrevation of waiting around all day for a service person.

Reply to
Howard Beale

I gotta agree with the folks that say it is most likely the breaker. If there were problems with the a/c, they would usually show up in much less than the 15min or so you say it runs before the breaker trips. First question: Is the wire at the breaker aluminum? If so, you may be able to just tighten the screws at the breaker, or you may need to take the wire out, cut an inch or so off(assuming there is enough slack) put anti ox paste on the wires and reinstall them. Also check where the breaker plugs into the panel and see if the connections are stating to get burned. If they are, hopefully you will have unused spaces where you can install a new breaker, and just leave the original one empty.If the connections look bad and all spaces are being used, maybe you can trade spaces with another breaker for something that sees less use, like the range. Forgot to ask another thing: Is this breaker in the main panel, or is it in a smaller box at the A?C unit, and what brand of breaker is it? Good luck Larry

Reply to
lp13-30

I fix some machines for a living that use fuses or breakers rated 20 amp. Its pretty common for fuses to physically overheat and blow from poor connections heating excessively. breakers trip the same way.

see switch wires melt from the same situation.

plus breakers are designed to become MORE sensitive as they age. learned that westinghouse used to make breakers and I fixed machines at their plant in beaver pa.

fascinating place

Reply to
hallerb

snipped-for-privacy@aol.com posted for all of us... I don't top post - see either inline ort believe it. at bottom.

Oh boy, do not pay attention to this guy.

Reply to
Tekkie®

When I fixed tv's, customers would ask me, Why did it break now?

I asked them, When would you have it break?

If you think it should give trouble before now, how much before now? A year? 2 years? Why not before then?

Reply to
mm

Got to agree with all you say. I had a GFI breaker that kept tripping. Of course I suspected I had a ground fault in something, but when I couldn't find anything plugged in all the time, I replaced the breaker and that solved the problem. The house was 7 years old. New one has lasted 20 years so far.

Reply to
mm

This is -- am I correct -- because the only reasonably priced alternative was that they become LESS sensitive as they age, and that would be dangerous.

When cars first had turn signals, turning the switch on didn't turn the light on until the flasher period had passed. In the 60's or 70's they changed it so that the turn lights came on as soon as the switch was turned on. That meant when the flasher failed, one could flash the lights using the switch.

Reply to
mm

What do you think the truth is?

Reply to
mm

Its INTENTIONAL more sensitive as age, by the design of the breaker components. my very best friend used to design power transformers for a living and he has talked about it too.

its the only safe way..........

High heat thermostats like cal stats are designed to have temps drop as they age its all in the interests of safety

Reply to
hallerb

try replacing breaker FIRST its low cost and proves the problem is in the AC unit.

if your afraid to tackle this ask around friends, its actually easy but turn main off before opening cabinet

Reply to
hallerb

Agreed. I did it and I'm definitely no electrician. Not really that hard to do. Just make sure you get a comparable circuit breaker, then just pay attention to how you remove the old breaker and how it was wired. Actually I'm making it sound harder than it is. The hardest part is just getting the comparable circuit breaker.

// doug // website: MyHomeRebate.com "Buy New Homes for Less in Texas"

Reply to
MyHomeRebate.com

mm posted for all of us... I don't top post - see either inline or at bottom.=20

I think the truth can be found on the standards organizations or manufactur= ers=20 sites - notably Square D. Holler Butt has spread SO much rumor and conject= ure=20 and opinion in his posts that the reasonable reader CANNOT BELIEVE ANYTHING= HE=20 STATES. When presented with facts he either ignores or goes off on a diffe= rent=20 tangent. Previous questionable statement have involved testing circuit=20 breakers by shorting wires and that faucets are designed to leak from the= =20 factory.

--=20 Tekkie

Reply to
Tekkie®

Oh, it sounded like you were saying that that particular statement he made, at the top, was false. Especially since you deleted everything else but that one sentence.

I'm afraid you risk losing credibility when you post like that after he says something which is most likely true. In this case I think it is obviously, totally true. The only other affordable alternative would be dangerous. So he was right and your criticism was ill-placed. If he keeps gaining a point and you keep losing a point, you won't be a position to contradict him even in cases where he's wrong.

Reply to
mm

HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.