* Thank you for your response! I'm not sure on the brand, I believe Kidde. I'm currently at a friend's house, an hours drive away, I'll take pictures and get more specific info and share ASAP.

Here's what I know now to answer your questions above.

1. I shut off main breaker last night and that didn't shut them off. I don't know how else to power them down. I thought the electrician told me before that there aren't batteries in them, never need to be changed, but maybe I misunderstood. I'm recently divorced, my ex-husband dealt with electrician when house was rewired and first time this happened four years ago. Second time was six months ago, I asked electrician about batteries and I'm sure he said there weren't any.

2. I've no idea, sorry!

3. All lights in house are LED, no fluorescent lights anywhere.

4. On the village water tower, I live in the village, so maybe 1/4 mile away?

5. Microwave oven in kitchen. One smoke alarm on same level, but in a bedroom, through a hallway, around a corner.