My main breaker keeps tripping. I have tried truning off many appliances or braekers to isolate the cause of the problem, but the main breaker continues to trip despite only having a few lights on and the fridge. I have not yet tried turning off the breaker for the fridge, for obvious reasons. None of the breakers in the breaker box trip, just the main outside breaker. Any thoughts.

The problem is random, occurring from 12 hour invervals to minutes. Last night I slept with just the ceiling fan (not the AC) and the power stayed on all night.

Could temperature in or out of the house be a factor?

Breakers do go bad. Perhaps nuisance tripping like yours is more common. On the other hand, if one doesn't trip when it should, maybe the house burns down and the cause is said to be electrical without further investigation. The fire may destroy the evidence. If you have say a 100 amp main, and others ranging from 15-40 amps, the main should never trip without one of the load breakers tripping unless there was a short right in the box. Shorts to trip a 100 amp or bigger breaker should create sparks, smoke, fumes, etc.

The fridge goes off when the main breaker goes off. When you are away, it could set all day off. I would replace the main breaker. When it comes to DIY projects, my bravery may cost my life some day. This might be a good one to cough up for a professional. You might start with asking him to check things and make sure it is the problem.

The hotter it is where the breaker is, the sooner it is going to trip.

Labman,

I did call in a professional. The main breaker was bad and had to be replaced. He opend the breaker to find that one side was bad. The wire leaving the mainbreaker and that side of the breaker we heating up.