We just put an addition on our home to create a small office. In doing so, we added five receptacles and three light boxes to two existing circuits--one which runs in our bedroom and the other in the living room. These two circuits shared a neutral and when the electrician came to bring the "new construction" up to code, he had to put an AFCI on the circuits, since the receptacles are in living space. Given that our old box was too small for the new AFCI breaker, he had to install a second box, which houses one lonely double pole 15V AFCI breaker. All was well. We passed our inspections with no problem.
Now, two months into using the office, suddenly the AFCI has started tripping. The strange part--it does it at times when we're not putting any load on the circuits. The first couple times we noticed it, it seemed to be each evening around 7pm. Typically it was when I was in the kitchen making dinner and my husband was outside doing yard work. Neither of us were using any of the receptacles in question. We would just spontaneously lose power in the bedroom, office, and living room. Next we started noticing it around 7am. Each time we'd reset the breaker and it would be fine for another 12 hours until the next 7 rolled around.
It seemed to stop for a couple weeks, and now in the last week it has started up again--and now it's multiple times a day. 7am, 9:30am, 2pm, 7pm. Like clockwork. We don't have any appliances in the house that are on a timer. Each time it's when we're not putting load on the circuit--if anything we're in other rooms altogether.
I'm loathe to call our electrician because we did not have a good rapport with him--I had started doing the electrical work on the house before I knew the city was going to require a licensed electrician. AFCIs are admittedly beyond my area of expertise, but I can't find any evidence of arcing in the receptacles. Is there any chance that our public power company could be experiencing surges that could set off the AFCI? What am I missing?
