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The Breaker switch to my AC in my home flips off intermittently. When this happens the main breaker flips as well. I had an AC guy come out and he says the ac unit is bad and needs replaced. The breaker only flips about once a day and the ac is running and cooling perfectly. Could it be a bad breaker or do I need to replace the ac?
Welcome. My name is XXXXX XXXXX would be glad to assist.
When you say it trips once a day, is there any repetition on the time it trips during the day? Or is it completely random?
What is it that the HVAC tech is stating is wrong as to why it needs replacing?
It trips and random times. He says the compressor its self is faulty.
He indicated it is not grounding properly and the unit might be locking up when causes it to pull more electric than it should
Compressors will definitely act that way when reaching their end of life. They are nothing more than an electric motor and when the windings begin to fail, they cause a high inrush at times and trip the breaker. Or if the pumping section is weakening, it will do the same thing.
I dont know what he means by "not grounding properly", compressors operate off 240 volts and dont use a ground.
Have you measured the inrush current?
Or just normal operating current?
I just don't want to replace the ac then have to call and electrician later to fix something else. I will ask him about the grounding. It is a 30 amp unit going to a 30 amp breaker that flips and his major concern was the main breaker to the house flipping at the same time the ac flips.
Ok, the main breaker, is it 150 or 200?
No i have not done anything. I was just confused about the randomness of the breaker tripping. I just thought if the ac was really bad it would flip every time it tries to come on.
What size is the main?
I am not sure. Its a small 2000 squire foot house so probally just 150
The main should not be tripping. The 30 amp to the unit should trip prior to getting to the main. I would be suspect on the 30 amp for sure, as it it should trip on any issue and there should be no current for the main to see after it trips.
Yeah that's what he said.
As for the compressor, under normal operating, when they START, they will pull 4-7 times normal. So when they are beginning to show signs of failure, either in the windings or the pump section, that amperage will escalate way beyond that number. That is why it is random and sometimes works fine. That is what happens and is to be expected.
If it is completely shorted, then it would trip everytime it starts
They should have documented on the service ticket, the start amperage and running amps.
Without that information, it is difficult to know what is happening. But the 30 should be replaced either way, even if you get a new unit. It is not operating properly
Ok, thank you. I will have an electrician come out and replace the amp then go from there.
Might also try a "hard start kit" on the ac compressor
Whats a hard start kit?
It is a beefed up capacitor to help it start without pulling high amperage
Sometimes they work somnetimes not, knowing what the amperage is now helps to determine if they will help
Ok will check it out