40 amp Square D 240 breaker

[CitadelBlue]

Evening all..... other than price $10 vs $22, whats the difference in these 2 breakers? Neighbor s AC unit keeps tripping the breaker and the AC guy says its the breaker. He currently has one that is solid on 1 side and a breaker switch on the other vs 2 switches linked together.

 

[wyliesdiesels]

Homeline vs QO

Different models

You need to get the right one per the panel nameplate label.

Is the panel homeline or QO?

QO is the one with only one handle

Also, i doubt its the breaker.

How long does it run before the breaker trips?

Whats the nameplate on the AC unit say? Can you post a picture?

 

[Bert_]

One isn't going to fit were the other belongs.

 

[CitadelBlue]

Humm.. thought I just had to get the correct brand.....Square D, vs GE vs Siemen etc. Didnt realize there were diffence models within the Square D brand. AC unit is a Carrier. AC repair guy says its the breaker. And the AC unit isnt but a month old. We ve had lots of rain these past few days in northern VA. Just wondering if there is water in something in the outside unit or fuzeable disconnect box. I ll ask my neighbor if the tech took the panels off and checked there.

 

[mike93lx]

It is likely only the breaker if the one installed originally was too small.

Are you looking to upsize or just replace? Breakers can fail, but it is rare.
Pleasr post the name place Pic requested

 

[Terry D]

On the outside condensing unit, there will be a label stating the maximum fuse or breaker size. This will let you know if the current breaker is sized to small. Is it tripping instantly or after it runs for a while

Sent from my SM-G960U using The Garage Journal mobile app

 

[CitadelBlue]

Discovered more on this. Seems even the old unit was tripping the breaker. Unit was replaced about a month ago and only recently started tripping the breaker again. I did not venture out across the wet ysrd this AM, but I have the same Carrier unit and it requires a 40 amp breaker. I replaced the 36 year old breaker and all seems well. Thanks for your comments and feedback.

 

[mike93lx]

Discovered more on this. Seems even the old unit was tripping the breaker. Unit was replaced about a month ago and only recently started tripping the breaker again. I did not venture out across the wet ysrd this AM, but I have the same Carrier unit and it requires a 40 amp breaker. I replaced the 36 year old breaker and all seems well. Thanks for your comments and feedback.

Amazing to think that a breaker could have saved the cost of a new system. That is like ultimate parts cannon ********

 

[Norcal]

Amazing to think that a breaker could have saved the cost of a new system. That is like ultimate parts cannon ********

The ultimate upsell, sell them a new unit & run. Know of a couple of times one local HVAC company that the tech released the refrigerant out of the unit to get the customer to buy new units, those times did not result in a sale for that company. They advertise on the radio a lot & still have to change stations when the adverts come on.

 

[bigdav160]

It happened to my sister. A/C quit so she calls a HVAC company she's used before and they sold her a whole new system.

The tech is there 2 days and he cannot make the new system work. The third day the supervisor come out and declares the new condenser/compressor bad and they'll have to order a new one.

So sis calls me up to take a look - - my diagnosis - bad breaker with one leg down.

 

[wyliesdiesels]

Humm.. thought I just had to get the correct brand.....Square D, vs GE vs Siemen etc. Didnt realize there were diffenece models within the Square D brand. AC unit is a Carrier. AC repair guy says its the breaker. And the AC unit isnt but a month old. We ve had lots of rain these past few days in northern VA. Just wondering if there is water in something in the outside unit or fuzeable disconnect box. I ll ask my neighbor if the tech took the panels off and checked there.

yes there are different models. The different models are not interchangeble.

Sq D has 2 different residential lines and so does Eaton as well as GE. Siemens used to but are phasing out the murray line.

 

[Bert_]

It happened to my sister. A/C quit so she calls a HVAC company she's used before and they sold her a whole new system.

The tech is there 2 days and he cannot make the new system work. The third day the supervisor come out and declares the new condenser/compressor bad and they'll have to order a new one.

So sis calls me up to take a look - - my diagnosis - bad breaker with one leg down.

That's why it's important to check for the voltage line to line. I run into many people who will check from line to ground. On a 240v appliance voltage line to ground means nothing.

 

[mike93lx]

That's why it's important to check for the voltage line to line. I run into many people who will check from line to ground. On a 240v appliance voltage line to ground means nothing.

Well, to be fair, it will tell you if that leg is good. Something, just not particularly useful on its own

 

[Bert_]

Well, to be fair, it will tell you if that leg is good. Something, just not particularly useful on its own

Not if it's calling for it to run. The one good line will feed through the motor and read 120 to ground on each side.

 

[mike93lx]

Not if it's calling for it to run. The one good line will feed through the motor and read 120 to ground on each side.

Oh fine, you got me. Look at Bert with the big brain

 

[Wrench97]

Discovered more on this. Seems even the old unit was tripping the breaker. Unit was replaced about a month ago and only recently started tripping the breaker again. I did not venture out across the wet ysrd this AM, but I have the same Carrier unit and it requires a 40 amp breaker. I replaced the 36 year old breaker and all seems well. Thanks for your comments and feedback.

If the old system was actually pulling enough current to blow the breaker, I have seen them that after repeatedly tripping get weak and trip sooner then they should. We had a welder circuit that use to trip all the time when the amperage was cranked up(too small a breaker/circuit for the welder was the issue) it finally got to the point that a 30 amp breaker was tripping as low as 15 amp.

 

[reader2580]

My uncle has a house built within the past five years. The central A/C unit started blowing the breaker a few weeks ago. The HVAC guy was out twice and finally said maybe the breaker is bad. It got to the point the A/C would run for less than a minute after resetting breaker.

My father went out there to replace the breaker for him. It turned out one wire was loose at the breaker and was burned up for several inches. My father fixed the wire and everything is fine now.

The moral of the story is don't just automatically assume an A/C unit tripping a breaker is a bad breaker.

 

[wyliesdiesels]

Sounds like the HVAC guy didnt do a good job troubleshooting