19

Note: I'm creating and immediately answering my own question because I wasn't able to find documentation of this solution online.

My condo is equipped with a FirstAlert 7010BSL smoke detector (technically mine is a 7010BSLA model; it appears identical to the 7010BSL). This model of smoke detector is hardwired (i.e., it uses mains/grid power) but also takes batteries to provide power during an outage.

My detector recently started beeping periodically to indicate that its batteries were low. I took out the old batteries and put new ones in, but the beeping continued. This is apparently a common problem with FirstAlert smoke detectors as the company has a dedicated help page for it.

Following the instructions on that page, I performed the following steps:

  1. Turned off the breaker connected to the smoke detector
  2. Disconnected it
  3. Removed the batteries
  4. Held the test button for 30 seconds
  5. Inserted new batteries
  6. Waited a few minutes
  7. Reconnected the detector
  8. Turned the breaker back on.

After this process, the detector continued emitting the low battery warning.

What might be the solution to this problem?

Reign of Error
  • 579
  • 4
  • 9

1 Answers1

28

The problem was that, when I initially removed the old batteries, I damaged one of the terminals within the battery drawer. All the terminals are thin metal plates that deform easily; there are no spring terminals.

When I repeated the steps described above but bent the terminal back into shape before inserting new batteries (between steps 4 and 5), the detector stopped emitting the low battery warning.

For reference, here's a photo of the damaged terminal:

Battery drawer with a damaged terminal

I damaged the terminal because the batteries fit very snugly within the battery drawer and I wasn't aware that they're supposed to be removed by pushing on plastic tabs on the back of the drawer. After being unable to remove them by hand I pried them out with a screwdriver, which damaged the terminal.

Use of the tabs to remove the batteries is described in the manual (excerpt below), but I didn't have a copy of it until I found it online later.

Manual excerpt describing battery removal

Hopefully this helps other people who also encounter this problem!

Reign of Error
  • 579
  • 4
  • 9
  • 5
    Just to add to the answer, smoke detectors usually have a ten year life(recommended to replace with new ones). – crip659 Nov 06 '21 at 20:36
  • 1
    Don't forget to mark your post as the answer. – Steve Wellens Nov 07 '21 at 04:40
  • 3
    @crip659: The detectors at my local shops (yes, all those that I've checked) look to have been on the shelf a decade or longer. No manufacture date anywhere in sight. Is there anything that one could check on a detector, or should I just buy them and test them over a smokey fire? – dotancohen Nov 07 '21 at 10:49
  • 1
    @dotancohen That they don't mention. Do imagine in most places(regulated) that the detectors turn over rate is decent. The ten years is only recommended and usually from when you buy and start using it. They don't die at ten years, but might start being wonky(going off when humidly goes up). – crip659 Nov 07 '21 at 11:23
  • @crip659 I see, thanks. – dotancohen Nov 07 '21 at 11:39
  • 5
    @SteveWellens: it's necessary to wait two days before accepting one's own answer, but I'll make sure to accept it once that period has elapsed. – Reign of Error Nov 07 '21 at 15:54
  • 4
    Regarding detector lifespan: many detectors now have their date (or at least year) of manufacture printed somewhere on or inside them; for example, my 7010BSLA has its year of manufacture printed on its upper surface (which is unfortunately hidden while it's attached to the ceiling). – Reign of Error Nov 07 '21 at 15:57
  • @crip659 Don't a lot of smoke detectors utilize radioactive materials? I imagine that half-life might be an issue for them. – nick012000 Nov 08 '21 at 06:27
  • @nick012000 that is the reason for the 10-year limit. Mine are going strong at about 25 years (and often get the toast test, so I know they really work). – Chris H Nov 08 '21 at 09:24
  • 1
    @ChrisH The half-life of Americium 241 (the typical isotope used in smoke detectors) is around 432 years - and that's just the half-life, there will still be a sufficient quantity in there to function for far longer than that. The plastic housing will degrade long before it does. The reason for replacing them is more likely due to the electrical components failing after a few decades. – Darrel Hoffman Nov 08 '21 at 14:53
  • @DarrelHoffman AIUI it's not the absolute loss of signal that's the issue, but an increased risk of false alarms caused by the reduced activity. The recommendation is based on old designs which ran closer to the edge of the operating envelope anyway; modern designs with their balanced detection system are far better – Chris H Nov 08 '21 at 15:08
  • 2
    @ReignofError the replacement data is actually required for them to meet the standards – Chris H Nov 08 '21 at 15:09