Battery Backup Guide

caution asked:


I have looked everywhere but they are just to expensive.I would like it to have battery backup.

chasnr asked:


In my basement I have three smoke detectors that are all hardwired to the electricity with battery backups. One of the detectors was chirping, so, I replaced the battery and put it back up. Well, it still chirps, but, it’s not the actul detector chirping, but from the ceiling hardwire. I have taken down the detector, and you can still here the chirp coming from the wired area where the detector was. I have even put the detector in another room to make sure. No other detector in the house chiprs nor carbon monoxide detector. It really is coming from the ceiling where the detector was. ?????