Solved the "Low Battery Zone 29" dilemma today.
My alarm system has been giving this error message for the past couple of days, causing the display panel to beep every so often. Often enough to be annoying anyway.
So I've been wandering all over the house, replacing batteries in the various window sensors as well as the motion detector sensors. Little did I know that there are glass break sensors attached to my ceilings as well. Never thought to look up. Ok, so problem solved, right?
Wrong! The lady from the alarm company gave me the whole schematic over the phone, all 46 zones, and #29 is supposed to be a glass break detector in my front room, but I'm looking and it's not up there. She says it has to be, or they wouldn't be getting the signal...
All of a sudden, I say, "Ivan!!!" when it dawned on me that more than half of the sheetrock ceiling in my front room had to be ripped down and replaced after Hurricane Ivan hit in September 2004.
Sure enough, I went up in the attic and there it was hanging from a nail that someone must have pounded into one of the ceiling joists to hold it temporarily (and to prevent it from getting damaged) when they were ripping down the damaged sheetrock... and then forgot all about it the next day when they hung the new stuff.
Pretty good battery life, if nothing else.