Several days ago, we had thunderstorms come through the area over a period of a few days. Just for an example, let’s say we had storms last Monday, Tuesday, and Wednesday. On Monday, we had a very close lightning strike. There was maybe 1/10th of a second between the flash and the boom, perhaps less. Just enough to notice they were not simultaneous. No problems with anything.
On Tuesday, we had some more storms. The lights blinked a few times, during the storm, but the power never went out. No problems with anything.
On Wednesday, we had another storm with a close lightning strike, but not as close as the one on Monday. There was close to a full second between the flash and the boom. The kitchen light (4 tube fluorescent) went out. At first, I though we’d lost power, but all the other lights were working. I tried the switch, but no luck. No light. So, I said, it’s probably the ballast, I’ll have to go to Lowe’s and get a new one. On Thursday, I found that the kitchen light was on a 3-way switch, with one in the dining room. If I turned the kitchen switch to the up position, the dining room switch would turn the light on and off. If the kitchen switch was in the down position, the dining room switch did not work (no light).
So, I knew the ballast was OK, but the kitchen 3-way switch was bad. On Friday, I went to Lowe’s, got a new 3-way switch, installed it and we are all OK now.
But, why did the lightning strike kill the switch. And, why that switch and nothing else in the house? As one additional bit of perhaps unrelated information, when I replaced the switch, I discovered that the ground wire was not connected. There was a ground in the switch box, but it was never connected to the switch. The switch had paint on it from when the kitchen was painted, and I broke that paint when I removed it, so I know the electrician who wired the house did not connect the ground on that switch (or that switch was not installed by an electrician, but wouldn’t installing the light switches be part of wiring a new house?).
Anyway, I connected the ground when I replaced the switch and all is fine, now. But, why did the switch fail?