I'm going bonkers! My smoke alarm started beeping this morning, and has been going all day. It's the battery alert, two beeps every minute or so. Trouble is, it's hard wired, I took the cover off and no battery. Looked the model up online, it's a built in battery - grrrr. OK, so I let it beep until about 6pm, then decided to cut the wires. Nothing changed!! The damned thing is still beeping. The sound is actually coming out of the ceiling beyond the mounting bracket!
It's actually a wonder that the upstairs neighbors haven't banged on the floor to shut up! LOL
Oh, and I tried flipping breakers, but none shut it off.