I have 10 year old house. A few days ago, the electricity of one section of my house went off. When I opende dthe circuit breaker panel, one breaker tripped. When I turn it on, it worked but I could hear buzz sound. When I turn it off, the sounds gone. When I turn it on, the sound on. I thought it is caused by bad circuit breaker, so that I replaced it. But the buzz sound still stays when the circuit breaker is on. I took out most of the equipments connected to that circuit but the sound remains. Also the lights are dimming from time to time. Do I have to change the panel? I would appreciate your advice.

Next time you get in that panel, shut off the main, remove the breaker and look at the buss. What you describe is a sympton that can appear when the buss has been arcing due to a loose breaker. Look carefully at the buss where the breaker attaches and see if there is evidence of burning / arcing. If so, stop using that space and have a qualified electrician evaluate the pane. DO ALL OF YOUR INSPECTING AND BREAKER INSTALLATIONS WITH THE MAIN BREAKER OFF.

Thank you very much Missouri bound. There is no sign of burning or arcing on the buss when I checked after your advice. Can I install the circuit breaker at the other site or should I change the entire panel? Thanks again in advance.