A.Rex Cauldwell, a master electrician in Copper Hill, Va., responds: Dimming of lights is not caused by a surge but by a lowering of voltage. When the full voltage and brilliance of the lights return, it just looks like a surge.
I would advise you to hire an electrician skilled in advanced troubleshooting. The problem with situations like these is that you have to be there when the dimming occurs to be able to isolate the cause. I once had to move into a house for a couple of days to troubleshoot an intermittent problem.
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