Hi,

We have a Kiddie KN-COSM-1B smoke detector. Of the past few months
since the basement rebuild we have slowly been replacing our old
hardwired alarms with the Kiddie models. The Kiddie model has CO/Smoke
detector built in. They are apporximately $50 at HD each.

Today I went to replace the third smoke alarm near the attic room,
when all the alarms went off. I removed the new alarm, but could not
get it to stop beeping and saying "Fire, Fire." I can only shut it up
by taking the battery up. When I put the battery back in it continues
to beep. At this point it is not connected to any AC, just the
battery. This happens will all 3 of the Kiddie alarms. The last
remaining regular AC alarm is not beeping or making any noise.

Would could be wrong, how can I shut the alarms up and put them back?
The batteries are new, as are the detectors.

Thanks!