I have a very strange problem with 3 different circuits failing but the circuit breakers are not tripping. The service to the house is 100 amps and there are 16 subcircuits each on their own 20amp square D breaker. My lights flicker on one circuit and within 10 minutes all 3 circuits (two are on the same center bar - #7 and #8, the 3rd is #3, not adjacent) go out but the breakers don't trip. The breakers are not tripped and there is no red indicator popped up. Turning the breakers off and then back on does NOT fix the problem. Waiting 20 minutes and the power is back on working all 3 circuits. These circuits will come back in 20 minutes whether I throw/reset the breaker. Makes no difference. The circuits will then work for about 3-5 days and then it happens again (3 time now). I feel the breakers and they all are cool (all 16 of them), no heat. I would think if it was just one circuit that I had a short in the circuit and after it cools it come back on, but they are all different circuits and there is no cross circuit wiring. This wiring was done new in about 1995 so it is all fairly new and they have run without a problem for the past 16 years. I'm stumped, hope you can help.

Could be a loose neutral connection in the utility feeder, meter, or panel. Could be a loose bus bar a connection or at the Main Breaker. In any case, the problem is something that I doubt you can find or repair yourself, and needs an electrician to troubleshoot and repair as necessary.

Have to agree with TK, Could be the Buss the breakers plug onto. A Meter will narrow it down and locate the problem. An Electrician may pull Breaker(s), to see if the buss is burnt.