(NGC) - What happened? Home fire alarm system.

[Gliderjohn]

We live in a 16 year old house with a wired in fire alarm detectors with battery backup. In the past we have set one off a couple times by the kitchen  but that was the only one that went off. This morning for 3-5 seconds all the alarms went off together. We were not cooking and could not find any other reason for the alarm. Been fine since. Any thoughts. Does get one's attention.
GliderJohn

[AJ Huff]

Ours are like Christmas lights. If one battery dies they all go off. PITA but I just replace all the batteries at once then.

-AJ

[cloudbase]

Just a guess, but I'm thinking possible RF interference inducing a momentary signal in a cable that initiated the alarm.
Was there a thunderstorm anywhere in the area, say within five miles or so?

[jrt]

It happened to our house one time at 4 in the morning.  Woke up my wife and myself.  Woke up the cat.  Woke up the neighbor to one side in their own separate, away-from-us, house.   Our daughter slept right through it.  She didn't even stir.
No idea why that happened.

[LowRyter]

when in doubt change the batteries

[Mike Tashjian]

Wired detectors with battery backup means they are normally house powered and all alarm when one trips.  Depending on what kind they are photo electric or ionization they can be nuisance tripped by spiders, bugs, dust.  But the real problem sounds like they have aged out.  I think most will have a date at which they expire, used to be ten years for most.  16 years out you should be considering changing them all.  Old ones should be recycled properly as they contain radioactive material. 

[gsf12man]

Our system has pulled that several times and it's always turned out to be small bugs. The detectors also just seem to go bad randomly (fault light comes on), but cheap enough to replace.

[elvisboy77]

Probably dead batteries combined with a brief power outage.

Not ALL hardwired detectors are networked, this is a relatively recent thing so check the model you have to see if that is true.  If networked then perhaps one is bad.

Honestly, at 16 years you have gotten your money's worth.  Replacement 120VAC units that are networked can be had for about $10 each.  Well worth the money.  I would stick with something like First Alert or Kidde.

[Gliderjohn]

Thanks all. I was not aware of the age problem. May be that as I have replaced all batteries during the last three months.
GliderJohn