Smoke detector problems

[R Clark]

Last night, the smoke detectors went off.  False alarm, just like two two months ago.  The detectors are not yet two years old; I replaced all of the original detectors at the same time since I didn't know how old they were (we bought the house in 2014.)

These are Kidde ionization detectors, Model i12010S.  There are 5 detectors and they are hard-wired and interconnected, I think.  The backup power battery in them is a sealed lithium battery not intended to be replaced.

Kidde's documentation on how these things work is slim; there's not much to go on in terms of troubleshooting.  A search on this issue after the last set of false alarms indicated that dust inside the collectors could cause a problem.  We live in a rural area and it's dusty, particularly with two years of drought going on.  I took all of the units down and blew compressed air through them.  Thought I had the problem solved, until last night.

These things only go off like this in the middle of the night; never in the daytime.

Does anybody have any experience with these things that might help me solve the problem?

I'm willing to throw these out and install new.  Are there any better quality units out there intended for DIY install?

Thanks in advance.

[Snipe Hunter]

How often is this happening. First, I'd call Kiddie and see what they say (I should have done that). They probably would have sent me new detectors.

You probably have a bad detector, I did. I bought a 6 pack of Smoke/CO detectors. One was bad and it would set off all the others. I disconnected one at a time (once a week) until I figured out which one was the culprit... It took about 6 months to figure it out. Kiddie sent me a new detector. Same sealed 10 year batteries.

Also, if you have an old detector on the same circuit as the new ones, it can cause problems.

[merced]

I've had the same problem with some First Alert/BHK detectors that were all replaced at the same time about 5 years ago.  I think they've gone through 2 or 3 clusters of false alarms, and yes, only at night.  I either read or was told by a CS rep that sometimes dust build-up can cause this.  I've gone around and hit them all with compressed air, but that didn't always solve the problem.  In any case, every time they went back to behaving themselves after 2 or 3 alarm events spaced over a few days, so I haven't done anything else to troubleshoot.

[R Clark]

How often is this happening. First, I'd call Kiddie and see what they say (I should have done that). They probably would have sent me new detectors.

You probably have a bad detector, I did. I bought a 6 pack of Smoke/CO detectors. One was bad and it would set off all the others. I disconnected one at a time (once a week) until I figured out which one was the culprit... It took about 6 months to figure it out. Kiddie sent me a new detector. Same sealed 10 year batteries. 

Also, if you have an old detector on the same circuit as the new ones, it can cause problems.

Thanks, Neil.  This happened one night two months ago.  They went off several times in short succession; I removed the detectors and put them in the shop building.  The next morning I did the compressed air "cleaning" and replaced them.  Last night was the first time since then.  I removed the one in our bedroom and banished it from the house, but then it occurred again 20 minutes later.  That time, I think the one that started the commotion was upstairs; it was the only that didn't have a solid green light on the front.  I'm not certain that characteristic flags the offender.

All of the detectors were purchased at the same time and all are the same model.  I don't know how these things work.  On the little schematic with them, there's a red wire that I "think" is common to all five.  Is this the wire that signals to all the detectors when one of them is going off?  Or do they have sound frequency detection and go off if they "hear" one of the other detectors going off?

At any rate, they're all in one pile out in the shop building.  I don't know if either I or LOML could take months of trying to figure it out.  I'm a light sleeper and don't sleep well to being with.  A device that misfires for no good reason really triggers my Extreme Humor Impairment Syndrome.

I've had the same problem with some First Alert/BHK detectors that were all replaced at the same time about 5 years ago.  I think they've gone through 2 or 3 clusters of false alarms, and yes, only at night.  I either read or was told by a CS rep that sometimes dust build-up can cause this.  I've gone around and hit them all with compressed air, but that didn't always solve the problem.  In any case, every time they went back to behaving themselves after 2 or 3 alarm events spaced over a few days, so I haven't done anything else to troubleshoot.

Neither LOML nor I can deal with just letting it pass.

[Snipe Hunter]

Thanks, Neil.  This happened one night two months ago.  They went off several times in short succession; I removed the detectors and put them in the shop building.  The next morning I did the compressed air "cleaning" and replaced them.  Last night was the first time since then.  I removed the one in our bedroom and banished it from the house, but then it occurred again 20 minutes later.  That time, I think the one that started the commotion was upstairs; it was the only that didn't have a solid green light on the front.  I'm not certain that characteristic flags the offender.

All of the detectors were purchased at the same time and all are the same model.  I don't know how these things work.  On the little schematic with them, there's a red wire that I "think" is common to all five.  Is this the wire that signals to all the detectors when one of them is going off?  Or do they have sound frequency detection and go off if they "hear" one of the other detectors going off?

At any rate, they're all in one pile out in the shop building.  I don't know if either I or LOML could take months of trying to figure it out.  I'm a light sleeper and don't sleep well to being with.  A device that misfires for no good reason really triggers my Extreme Humor Impairment Syndrome.


Neither LOML nor I can deal with just letting it pass.

iirc... The red wire is a signal wire (iirc). I don't think the signal is on/off. I think might be something like a voltage or ohm/resistance change. I also believe a problem in the wiring can cause this problem. How do I know? Because once I figured out which detector was firing off the others, I cut the red wire and the problem stopped. So that one detector won't talk to the others. When Kiddie sent me the new detector, I reconnected the red wire and all is good.

I haven't seen this first hand but I have read in inspector forums that wiring can also be faulty and cause this. Old wiring on older (less finicky) detectors didn't have the problem but when new detectors were installed, they had false alarms. This makes me think there may be some sort of an ohm/resistance change which signals the other detectors. Never researched it but you are not the only person having this problem. More common than you might think.

[R Clark]

iirc... The red wire is a signal wire (iirc). I don't think the signal is on/off. I think might be something like a voltage or ohm/resistance change. I also believe a problem in the wiring can cause this problem. How do I know? Because once I figured out which detector was firing off the others, I cut the red wire and the problem stopped. So that one detector won't talk to the others. When Kiddie sent me the new detector, I reconnected the red wire and all is good.

I haven't seen this first hand but I have read in inspector forums that wiring can also be faulty and cause this. Old wiring on older (less finicky) detectors didn't have the problem but when new detectors were installed, they had false alarms. This makes me think there may be some sort of an ohm/resistance change which signals the other detectors. Never researched it but you are not the only person having this problem. More common than you might think.

Thanks...very helpful post to give me an idea about which way to take this.  I could disconnect all of the reds and make each stand alone.  Once one shows out, then I could reconnect others and gradually rebuild the system.  Those connections are made at each individual smoke detector box by a wire nut to the red wire backbone.  Easily reconnected if this turns out to not be possible for some reason.

The configuration of our house makes this possible.  The smoke alarms are vertically spaced in an upward line from the basement through the first floor and to the second floor.  Any single one of these alarms can be heard by us in our bedroom.  Neither of us are hard of hearing and we don't sleep very deeply, so I'm not concerned about risk of the detector in our bedroom not going off if another detector begins sounding the alarm.

[firefighter]

I had one that would false trip. No rhyme or reason to explain it.

Finally tracked it down to a cut in the vapor barrier. Allowed fine blown in insulation to filter down. Got into the detector causing an alarm. Some tuck tape to seal the cut and no more false trips.

Now if I could teach the wife not to burn bacon..........

[R Clark]

I disconnected all of the detectors from the "backbone."  That was two days ago and I got them all reinstalled in stand-alone config.

While reinstalling one of the upstairs units, I noted that the green light on front did not come on.  It was as if there was no AC power to the unit.  Multi-meter showed that 120V was available at the modular plug.  It took some fussing around with how the plug seated onto the prongs of the detector, but I finally got power to the unit.

Last night, one of the detectors went off again, this time at about 11:30 pm.  Why this only happens in the middle of the night, I don't know.  The offending unit was the same detector that I had trouble getting powered up.  I removed that unit and will continue to operate the rest in stand-alone mode for a while.  If I don't have any more false alarms for a period (TBD), I'll hook them all up again, and I'll see if I can get a replacement of the same model to replace the one I currently think is defective.

[Snipe Hunter]

I disconnected all of the detectors from the "backbone."  That was two days ago and I got them all reinstalled in stand-alone config.

While reinstalling one of the upstairs units, I noted that the green light on front did not come on.  It was as if there was no AC power to the unit.  Multi-meter showed that 120V was available at the modular plug.  It took some fussing around with how the plug seated onto the prongs of the detector, but I finally got power to the unit.

Last night, one of the detectors went off again, this time at about 11:30 pm.  Why this only happens in the middle of the night, I don't know.  The offending unit was the same detector that I had trouble getting powered up.  I removed that unit and will continue to operate the rest in stand-alone mode for a while.  If I don't have any more false alarms for a period (TBD), I'll hook them all up again, and I'll see if I can get a replacement of the same model to replace the one I currently think is defective.

I'll betcha they replace it without any issues. They did for me. I think we have the same detectors.

[Allen]

I disconnected all of the detectors from the "backbone."  That was two days ago and I got them all reinstalled in stand-alone config.

While reinstalling one of the upstairs units, I noted that the green light on front did not come on.  It was as if there was no AC power to the unit.  Multi-meter showed that 120V was available at the modular plug.  It took some fussing around with how the plug seated onto the prongs of the detector, but I finally got power to the unit.

Last night, one of the detectors went off again, this time at about 11:30 pm.  Why this only happens in the middle of the night, I don't know.  The offending unit was the same detector that I had trouble getting powered up.  I removed that unit and will continue to operate the rest in stand-alone mode for a while.  If I don't have any more false alarms for a period (TBD), I'll hook them all up again, and I'll see if I can get a replacement of the same model to replace the one I currently think is defective.

You might swap the suspect unit to a different location. If it goes off again you will know it is the unit and not some other problem.

Al