... out of the way, when the wired ones were installed?

But then that would be one heck of a battery.

=========

LOL

Then it suggests that there is another alarm up there that has a low battery.

the sound is so short, intense, and bounces around so much that it can be very hard to locate the actual source of the sound. Look around to be sure there's not another detector hidden in an inobvious spot.

Otherwise, I'd look into the attic. Maybe there's one up there.

n/t

house. Finally, found the fire detector I had stuck in a kitchen cabinet for some reason. I tried everything to pinpoint where it was coming from, but could not.

I ask because I deal with this in tech support all the time, with a customer cursing me out for twenty minutes because I won't help them with the sound that is unmistakably coming from their alarm, until they power down the alarm and realize it was a battery backup for something else.

The sound is often a quick, high-pitched chirp difficult to localize, so if one concludes early on that it's coming from a certain device, then it can be hard to hear where it's really coming from afterward.

What kind of ceiling is it? Is this an apartment? What's upstairs?

On a side note, new electrical codes typically require that all line powered smoke detectors in a residence "daisy-chained" together so that if one goes off, they all go off.

However, it is likely another smoke detector in the house that does need a battery replacemeny. It is hard to tell where those chirps are coming from. I would check them all and replace the batteries in all thst have them

House was constructed in 1984 by single family builder who was the largest in the city at that time. Most city inspectors were incentivized to look the other way. I know....used to work for the builder.

I agree that the chirping can be misleading but we have made SURE it is coming from that area. Only one other hard wired detector in the home and it is way across the house and NOT chirping.

We are two old and fat ladies and cannot access attic. But still why is this thing, if wired, not stopping when breakers are turned off?

Not because the breaker is or isn't tripped.

If indeed a smoke detector is at issue, then the chirp may go one of two ways if left unaddressed: it will either stop chirping once the battery is completely dead, or it will continue to keep chirping indefinitely because it's drawing on AC power from the building.

Do you have a centralized alarm panel to go along with the smoke detectors? You might, or you might not. If you do, then it should tell you which device is at issue; if it indicates no problem, then at least you know that it's not the system's smoke detector but rather some additional, independent device.

Been googling but not knowledgeable enough to understand.

separate the wires that led into the alarm about 6" back from where they came out of the wall (pulled the bundle out further into the room, unwrapped and separated them) and put the plastic screw on caps on each wire. It stopped. Have no idea what is going on. Good luck.

This is obviously something out of the norm.

Are there any mechanicals (furnace, air handler) in the attic?

An old, no longer used security system. We are idiots and we can't find the source for what we think is powering the chirp. We can't get into the attic. Too old and fat.

Electrician coming Tuesday. Darndest damn thing.

This house was a rental for many years and there was actually some high-end drug dealers living there for a time. This was over 20 years ago. They had cameras everywhere for security. Prob have something wired up in the attic that just now decided to make noise.

I say high-end drug dealers because the FBI raided them one night. Not local PD.

but did you ever figure out what the chirping was from?