I know that when you hear a periodic chirping noise from smoke detectors, it means the battery needs to be replaced. I had been hearing such a chirping noise in my apartment building for a few hours, and just realized that the sound is not coming from the smoke detector(s), but from the hard-wired horn/strobe device in the hallway.

What could be causing this? To be clear, the alarm is not going off - it is making the exact same sound as a dying smoke detector, but from a hardwired SpectrAlert Classic horn/strobe device. We did just have an intense lightning storm in which the neighboring building lost power. Could the panel have been hit by a surge?

  • 2
    Even wired alarms have a battery backup in case the power goes out. It is likely a dead battery.
    – fixer1234
    Apr 30, 2017 at 2:47
  • Do you have access to the panel itself to see if it's displaying a trouble light/indication? (It may be in a front entryway or atrium area in your apartment building -- even though it's in a locked case, the display/indicator lights should be visible still) Apr 30, 2017 at 3:01
  • This is not a wired smoke detector though - it's a horn/strobe alarm: i.ytimg.com/vi/jcvkgkRVCNU/maxresdefault.jpg (Not an actual picture)
    – Derek
    Apr 30, 2017 at 3:06
  • 1
    I doubt it is a battery because every alarm in the hallway is making the same sound. I think the panel is in the back of the building in a utility closet - I can hear a distinct beeping back there.
    – Derek
    Apr 30, 2017 at 3:11
  • 3
    I'd hope by this point you've spoken to building management about this, as a fire alarm in communal space is probably their responsibility.
    – Ecnerwal
    Jul 3, 2017 at 13:40

4 Answers 4


Whoever's in charge needs to check the panel

I will admit that it'd be odd for notification appliances to be making noises due to a trouble condition, but it is conceivable that they could do so, especially if the notification appliance circuits are more sophisticated than a simple polarity-reversal system with horns attached. Whoever's in charge of the panel needs to check the annunciators for a trouble or supervisory condition and correct it. It could be a flat battery, damaged wiring, a supervisory switch that's mis-set, or any number of other conditions -- the panel should say more about what precisely is going on, considering this is a central station fire alarm system with a central control panel that will likely have a display, etc. (vs. a bunch of smoke alarms wired together).


Even the wired smoke alarms have a end of life date. They start to chirp when they are not functioning up to spec any more. This can be caused by accumulation of particles on the sensor (from smoke, fumes, etc.) When one of mine starting chirping (single beep every few minutes or so), I took it out and noticed that the install date was about 8 or 9 years ago, for a product that was supposed to last 10 years.

You can probably remove it from the base plate and look at the back side. There should be a manufacture date on it and instructions regarding how long the device should last. If it is anywhere near that date plus the expected product life, then replace it.

I would replace all of the smoke alarms in the house at the same time if they have similar dates on them. These things start chirping at most inopportune times. (Seems like they know when it is most annoying). The safety of your family is worth it, and knowing that they are all good is peace of mind.

  • 1
    he's dealing with an actual NFPA72 central station alarm system here -- this is a whole another can of worms than single or multiple station smoke alarms May 1, 2017 at 2:33
  • I am planning to check the EOL dates on the smoke alarms, but it is NOT the smoke alarms that are chirping. It is the wall-mounted red horn/strobe alarm, and it's every one of them in our building. Building mgmt. is going to look at it today. I am just curious what (dead central battery, power surge, dead panel or NAC) would cause the system to do this.
    – Derek
    May 1, 2017 at 16:05

If it's managed by a service (like an ADT) I would contact them first. Additionally the system may have actually lost power and is currently running on battery and there is a tripped circuit breaker from the storm.

  • This is an apartment complex situation, so it's building management's job to fix. Sep 5, 2017 at 2:33

You should disregard all these past comments...

Contact property management, and tell them what is going on. They need detail to give to the fire protection company that services the property. The more details the better. For example is the dryer or AC turning on, what time of day or night, find the patter if possible. This issue is normally due to lighting damaging the building panel causing the NAC circuits to false activate for a split second. Also a main contributor if high voltage bleed over to the low voltage circuit. When an influx of power is drawn to the high voltage circuit, in some cases it can bleed over giving a small bursts of power to the NAC circuit. I can go into a lot more detail but no need. I have a Nicet level 4 in Fire Alarm and run a large FA service company.

  • Lightning you mean? Sep 1, 2021 at 1:49
  • Your experience in running a service company will be most helpful over time, so please do contribute more, it'll be appreciated. I'm sure you noticed that the question was 4 years old (not that new info is bad), and that that your advice to "contact property management" was advice given 2 of the 3 answers prior to yours and comments, so I'm sure that disregarding that isn't really what you'd intended.
    – FreeMan
    Sep 1, 2021 at 15:21

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