AC tripping breaker, help

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Thank you for your help. My supply house had a GE 45 amp breaker for $17, I was shocked. I t seems a little better in that the new breaker doesn't trip the instant you turn it on like the old 40 amp one did sometimes yesterday. But it did hum, and the old one buzzed louder. Lights still dim.
 
First, I would check the contacts on the compressor contactor and check all the wiring from the panel to the compressor itself (could have a loose wire in the compressor doghouse very common)

If the connections are good adding a hard start kit should make it work and change the existing run capacitors. Get the #s off the compressor and the run cap and go to any ac supply house and they can fix you up or have the AC guy do it. They make hard start kits with the capacitor and relay and you just plug two wire in. It's really his job if you have good wire and a good breaker the problem is in the ac.
 
. Owner says he had his HVAC guy check it and said it was fine.
Take that statement with more than just a grain of salt.
Got a call from a customer that was getting a new HVAC installed. Contractor (supposedly "experienced", company long established in area), couldn't figure out which breaker was for the existing furnace, (older house, multiple taps, several MWBC, rag wire and ungrounded BX) so he intentionally created a dead short to try to trip the breaker. Several lights and other outlets went dead. (That's when the customer called me in.) Tech said there was no breakers tripped. (But the furnace had no power so he just continued with the install.) He apparently never considered using a ticker and just turn off circuits until the ticker stopped.
 
I would be concerned if the new breaker still hums.

1- is the 240v line continuous from breaker to disconnect? What gauge is it?
2- Are the electrical connections tight from breaker all the way to the compressor? You could have a loose spade connector at the compressor terminal or even in the disconnect.
3- when was the last time your HVAC system was cleaned and charged? Someone could have thought the system was low on refrigerant and dumped half a tank into it.
4- As others have mentioned, did your HVaC tech check the run capacitor? What about the start capacitor?
5- Did the HVAC tech tell you the ohms of the compressor and condenser motor?
 
The A/C breaker should be in the main panel, near the main breaker, if it isn't.

I've always wondered about putting the highest current drawing breakers nearest the main breaker. Was it really necessary, did it actually accomplish anything, or was it something done simply because that's the way we've always done it and nobody really questions it?
 
I've always wondered about putting the highest current drawing breakers nearest the main breaker. Was it really necessary, did it actually accomplish anything, or was it something done simply because that's the way we've always done it and nobody really questions it?
I don't think it makes any real difference. Electricians believe in all kinds of myths like this one. I don't worry too much about trying to correct their thinking because it just doesn't really matter where the circuit breaker is physically located.

Personally I am a fan of putting the largest loads first just because that's the way they're typically done on schematic drawings of control panels. I don't know why it's done that way but that's typically the way it's been done for as long as I can remember.
 
He says it started doing these two things after we worked there. He is getting ready to sell and had asked us to make the house code compliant. Several twins (tandems) were in the panel that did not allow twins. Plus someone had added a wide variety of breaker brands over the years. And this 200 a panel was one of the most crowded packed panels I have seen. ............................. Owner says he had his HVAC guy check it and said it was fine.

Sounds like a desperate man trying to get you to fix all the hack work done over the years, probably without permits, because now that he is selling he has to get it inspected for real. At least that's the impression I get from your description.
Is there a way you could see what electrical permits were pulled for the property in the past?
 
Sounds like a desperate man trying to get you to fix all the hack work done over the years, probably without permits, because now that he is selling he has to get it inspected for real. At least that's the impression I get from your description.
Is there a way you could see what electrical permits were pulled for the property in the past?
Around here you can get a list of the permits that were pulled for a property from the tax assessor's office. In fact you can look it up online. The primary reason for permits is so that they can raise your taxes, so it's not surprising the tax assessor has this information.
 
I've always wondered about putting the highest current drawing breakers nearest the main breaker. Was it really necessary, did it actually accomplish anything, or was it something done simply because that's the way we've always done it and nobody really questions it?
I don't think it makes any real difference. Electricians believe in all kinds of myths like this one. I don't worry too much about trying to correct their thinking because it just doesn't really matter where the circuit breaker is physically located.

Personally I am a fan of putting the largest loads first just because that's the way they're typically done on schematic drawings of control panels. I don't know why it's done that way but that's typically the way it's been done for as long as I can remember.
Yet there is panels with sub feed or feed thru lugs. The panel bus is nothing more than a short length of feeder and the breakers are just taps off that feeder. If there is significant losses in a few inches of bus you have a serious problem or extremely under sized bus.
 
I also like the way it looks to stack the 2p breakers on one side, and 1ps on the other.

It just looks more like they were placed on purpose than random placement does.

DSC00850.JPG
 
I also like the way it looks to stack the 2p breakers on one side, and 1ps on the other.

It just looks more like they were placed on purpose than random placement does.

View attachment 2561461
A lot of times the two pole breakers are used for lights so it's handy to have them on one side so that you can just start at the top and flip a bunch of them off going down, and not have to hunt for them.
 
To the o.p. this is when its best to just be an electrician and verify volts and good connects , then get the heck outta there. Assuming you didnt change anything out of our scope...
 
I t seems a little better in that the new breaker doesn't trip the instant you turn it on like the old 40 amp one did sometimes yesterday. But it did hum, and the old one buzzed louder. Lights still dim.
I would be concerned if the new breaker still hums.
So would I. There is still a problem. Maybe the buss section where the breaker is plugged in is arced and pitted. Who knows maybe another bad breaker.
 
So would I. There is still a problem. Maybe the buss section where the breaker is plugged in is arced and pitted. Who knows maybe another bad breaker.
If it hums during starting of a motor load, I don't get too concerned. Still humming after it reaches full speed might be something wrong with it, or motor current never dropped to normal run conditions could mean something wrong with motor or drive load and it still is drawing too much and tripping could be expected. Single phase motor with capacitor problems could do what I just mentioned.
 
Around here you can get a list of the permits that were pulled for a property from the tax assessor's office. In fact you can look it up online. The primary reason for permits is so that they can raise your taxes, so it's not surprising the tax assessor has this information.
Or that no permits were pulled for any of the work done.
 
If it hums during starting of a motor load, I don't get too concerned. Still humming after it reaches full speed might be something wrong with it, or motor current never dropped to normal run conditions could mean something wrong with motor or drive load and it still is drawing too much and tripping could be expected. Single phase motor with capacitor problems could do what I just mentioned.

That is exactly what happens when the capacitor is defective. Change out the capacitor ! ...
 
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