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Smoke detector faulse alarms

KaiserRoo | Posted in Energy, Heating & Insulation on May 2, 2006 07:18am

Hello to all,

My wife told me that over the past 4 days the smoke detector has gone off 3 to 4 times for a minute or two at a time with nothing going on at all. I’m about to check them out but was wondering what might be causing it.

I’ll post again once i have the manufacturer and model number. I’ve got one in the stairway that goes from the basement to the 1st floor. One on the 1st floor and one on the 2nd floor. All are hardwired together with battery backup.

PS they seem very, very sesitive going off when my wife is using the oven. You can not even smell any smoke, and the oven was just cleaned and it still goes off.

KaiserRoo 

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Replies

  1. User avater
    BillHartmann | May 02, 2006 07:27pm | #1

    The first thing to do it to take each one down and blow out any dust.

    1. KaiserRoo | May 02, 2006 09:07pm | #4

      Here's some info on the detector

      BRK electronics (smoke and carbon monoxide alarm) this is on the front cover but on the back it reads First Alert model# SC6120B. It looks like it was made Jan 08, 2003 and I've had it for about 2.5 years.

      I removed and checked all units and could find little or no dust, bugs or anything else.

      KaiserRoo

      1. bosn | May 03, 2006 06:44am | #6

        Is it happeniing after dark?   Had a house once where these bug moths were fluttering around the small lights on the detectors and setting them off with the dust from their wings.There are no electrons!  It is all made up.  Don't believe it.

        Electricity is made by GREENIES.

      2. User avater
        McDesign | May 04, 2006 02:33am | #14

        A house up the street has such a bad radon problem in the poured full basement that they can't leave for the summer without cutting off the CO detectors - falsing all the time, once there is no circulation in the house.

        We've got a big radon issue here, but this old guy, a retired engineer from NY, came down and "knew the right way to build a house".

        He's got some air quality issues, as well - it's sealed up like a drum!

        Forrest

  2. DanH | May 02, 2006 07:41pm | #2

    There are two basic types of smoke detectors -- photoelectric and ionization. The ionization type are most prone to false alarms.

    There are also various grades of smoke detectors, from the real cheap ones to ones running $100 or better. The better quality ($20-30) ones will generally have fewer false alarms.

    In this case, take down the detector and, as suggested, vacuum it out. Also replace the battery. Check the age of the detector (it should have its manufacturing date stamped on the back, or better, the date of installation written on the label). Detectors should generally be replaced every 10 years or so.

    If this doesn't fix it, see if you can find a photoelectric unit to replace the one you have (which is almost certainly ionization). The PE units are hard to find, though. (You can tell the difference because the ionization units will always have a notation on the back that they contain nn microcuries of radioactive isotopes.)

    Also (especially if you can't find a PE unit), look for a "kitchen" smoke detector. These are generally set up to have fewer false alarms, and usually have a "silence" button.

    If Tyranny and Oppression come to this land, it will be in the guise of fighting a foreign enemy. --James Madison
    1. KaiserRoo | May 02, 2006 09:19pm | #5

      Dan,

      It is a unit with the ionization. I'd have to get three new units as they are tied into one another. So, what unit is better than another.

      KaiserRoo

  3. DanH | May 02, 2006 07:45pm | #3

    Also, if you can figure out how to do so, temporarily disconnect the detectors from each other. This involves disconnecting the "common" wire on one of them. (Only do this if you're comfortable working with electrical circuits.)

    With them disconnected it's a lot easier to figure out which one is acting up.

    Note that since they are connected together, you generally need to replace both of them at the same time if you change styles, and if you want to preserve the simultaneous alarm feature.

    If Tyranny and Oppression come to this land, it will be in the guise of fighting a foreign enemy. --James Madison
  4. cap | May 03, 2006 09:23am | #7

    The dust suggestion is a good one, but if you cleaned them and it's still happening--it's probably the battery in one or more going bad.  The intermittant signal is your cue to change the batteries.

    Cliff

    1. User avater
      BillHartmann | May 03, 2006 06:48pm | #10

      If it is a battery then the unit is defective.A low battery should give a periodic "chirp" at regular rate.He report 1-2 mintues of alarm at random times.

      1. DanH | May 03, 2006 06:55pm | #11

        With some AC units the random alarms can be caused by electrical interference.

        If Tyranny and Oppression come to this land, it will be in the guise of fighting a foreign enemy. --James Madison

  5. ronbudgell | May 03, 2006 01:26pm | #8

    I can add a couple of things to the suggestions above:

    First, heavy pollen dust in the air can sometimes set them off

    Second, I have a unit which is mounted in a low ceiling near a door which swings under it. If the door is left open directly under the smoke detector, the reflection from the top of the door is sometimes enough to set off the alarm.

    Ron

  6. arrowpov | May 03, 2006 05:58pm | #9

    Check the back-up batteries as the get low you will get intermittent beeps.

  7. chile_head | May 03, 2006 07:32pm | #12

    Are you sure it's tripping the fire alarm and not the CO alarm?!?

    1. Rebeccah | May 03, 2006 10:08pm | #13

      ---Are you sure it's tripping the fire alarm and not the CO alarm?!? ---You beat me to the question.My CO alarm started beeping erratically when it went bad. The CO sensors don't last forever. As I recall, it was *not* the slow chirp of a dead smoke alarm battery.

  8. RenaissanceRestorations | May 04, 2006 02:56am | #15

    Power surges / fluctuations will cause the detectors to trip once in a while. My next door neighbor installed a hot tub, and every time the pump kicked in, the smoke alarms would chirp on my house. Seems the hot tub wasn't installed "to code", and the service feed wire needed to be replaced, wiring to the pole was ancient..

    F

    1. KaiserRoo | May 04, 2006 03:47am | #16

      Thanks to all for the help, I wish I could get my dog to tell me if it goes off when we are away.

      KaiserRoo

      1. northeastvt | May 04, 2006 04:24am | #17

        KaiserRoo,

          Have you checked for CO,and ruled it out? After that blow the dust out of them or switch detection type.

         Northeastvt

      2. carbon | May 04, 2006 03:24pm | #20

        Are you sure it's the alarm? You might want to put another one in the room and see if it goes off too.

        1. chile_head | May 04, 2006 04:30pm | #21

          On kind of a similar note, does anyone know of a smoke alarm that isn't *really* sensitive. I have one in my basement that that goes off really quickly. Rip a 2X, it starts beeping. ( I'm using a sharp rip blade, and my blade is parallel to the fence.). Use the grinder for more than a couple of seconds, it goes off. The problem is, it's a hard wired smoke detector, and I wind up just pulling the breaker to shut it off, which obviously isn't the best solution, since it kills the rest of the house, too. Does anyone know of a brand that is a little less sensitive and/or has a mute button?

          1. User avater
            BillHartmann | May 04, 2006 04:35pm | #22

            It is more than the brand, but also the type and design.First of all there are two types of smoke detectors, plus heat detectors. There are ionization based alarms and photocell alarms. One is more sensitive with smoldering fires and the other one with open flames.And yes they come with mute buttons.But the all of the units on a hard wired system need to be compatible.I would first check with the manufacture of the brand that you have and see which type your dector is and what other ones are available.

          2. DanH | May 04, 2006 04:48pm | #23

            About 15 years back I was redoing our upstairs bath. Used a hot air gun to soften the old flooring adhesive, and the colorless fumes produced kept setting off the ionization detector just outside the bathroom door. Later on, while soldering some pipes for the shower, managed to start a small fire and fill the bathroom and hallway with smoke. Not a peep out of the smoke detector.
            If Tyranny and Oppression come to this land, it will be in the guise of fighting a foreign enemy. --James Madison

          3. BryanSayer | May 04, 2006 06:09pm | #25

            Ours had little "shower caps" on them during construction. Perhaps it would be easier to just cover it while you are working. Be sure to do something that makes you remember to remove the cap, like put a string across the door or something.

  9. kcbuilder | May 04, 2006 06:57am | #18

    In my real job I am a firefighter and might lend some expertise in this area.. MIGHT... As previously mentioned you want to blow out or vaccum out all of your smoke detectors.  Usually there is a little dust that gets  in the detector and sets off a false alarm. Spiders are also a common problem.  You can usually check the different detectors and the one with the solid light or the one that "looks different" as far as the light goes is the culprit.  As far as the CO detector and smoke alarms combo goes.. Get a seperate CO detector with a digital readout.  I belive that first alert makes on that you can plug into an outlet with a battery backup.  As mentioned earlier in this thread 10 years is about the lifespan of a detector and changing the batteries when you change the clocks in the fall in spring is a good idea.  Hope you find out the problem and am excited that some people actually pay attention to the white little round things on the ceilings.. They do save lives...

    Eventually every fire will go out...
  10. Norse | May 04, 2006 03:22pm | #19

    I've got one in the stairway that goes from the basement to the 1st floor

    Does this mean you have a smoke detector in the basement? If so, change it to a heat detector. Moisture and bugs will give you false alarms.

    Norse

  11. BillW | May 04, 2006 05:41pm | #24

    My new attitude is that there is no such thing as a false alarm - they go off so rarely that I figure there must be SOME source of smoke (or CO in your case).

    A tenant called me a couple months ago to tell me the alarms had gone off briefly at 2am, then stopped (she waited till a decent hour to tell me).  I went over, tested them all, took the covers off looking for dust / cobwebs / spiders, found nothing.  Figured it was a false alarm.

    The next day she called to say she had no hot water.  I didn't connect the two things in my mind, but went over to see what was up with the electric HW heater.  Took the covers off and found an electrical open - a wire had come loose, arced, burned some insulation and plastic, and vaporized.  The circuit didn't even trip (since the wire basically acted as it's own breaker).  This was a one year old unit btw.

    So if it was me, I would assume you have a real problem and hunt till you find it, usually techniques others have suggested to isolate the problem.  But then again, if you were me, who would I be?

  12. DoRight | May 04, 2006 11:52pm | #26

    WE had one that went off whenever we showered.  Go figure.

    We had another one that went off if we turned the heat in the house down below about 58 degrees.

    If they are old replace them.  They are cheap.

    1. KaiserRoo | May 09, 2006 03:31am | #27

      Update on false alarm problem.

      Well I got to hear it myself this weekend. All units (can't tell which one is setting them off) went off around 3pm on Saturday. It went off like it had detected smoke (not replace battery, not CO) for one minute and then stopped. Nothing was being cooked or anything else that we felt would account for the alarm.

      I checked all the batteries with the tounge and then with a volt meter. All tested to 8.5 volts. In addition I removed and blew out the three units using a compressor.

      KaiserRoo

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