Latest Discussions : Electrical & Lighting


08:29PM | 05/26/06
Member Since: 05/25/06
3 lifetime posts

I could not find an obvious way to edit my post and I need to make a couple of corrections/clarifications.

First, it looks like our original BRK smoke detector was a photoelectric detector, not an ionization detector. Our current detector, a Kiddie Nighthawk (spelled Kiddie wrong the first time) is an ionization detector.

Second, does the housing up in the ceiling that holds the wires for the detector have a speaker or amplifier in it that is allowing us to hear the beep when no detector is connected?

We have a theory and would appreciate any feedback:

The original BRK detector was old and went bad, somehow losing its connection to the other detectors in the house and so causing the periodic chirping. Please note, the chirping never has been continual.

We put a battery operated detector up there and that does not stop the chirping because it is not connected to the wires, so the system still detects an interrupted connection somewhere and chirps.

Is this possibly our issue? If so, will finding another BRK hard-wired detector and putting it up there solve the problem?

Thank you everyone.


04:42AM | 05/27/06
Member Since: 04/25/05
1915 lifetime posts
No way can the wires/connector make the sound.

And I don't know of any normal installation that would include anything else in or around the box.

I suspect that the sound is something completely different. Something in the attic and it is "coming though" the box as it is penatration into the otherwise "sealed" ceiling.

Go into the attic and check it out.

Also get some foam in a can seal the back side of the box.

And look around and see if there is anything around the box. The previous owner might have installed something else. Maybe a home rigged alarm for an open garage door or somethign like that.

But the main too things that I can think of would be a bad bearing on a wind turbine roof vent. Or a it you have HVAC equipment in the attic a bad bearing on the fan or fan motor.

Either one will make "somewhat" random sqeaking/chirping sounds.

Lets us know what you find.


09:09AM | 05/27/06
Member Since: 03/31/05
265 lifetime posts
Look for a smoke detector that has been installed in the attic. Take it out, you do not need one there.

Find the breaker that controls the detectors and turn it off. See if the chirping continues. If so, look for a bad turbine bearing, bird nest, other critter nest.


09:39AM | 05/27/06
Member Since: 05/25/06
3 lifetime posts
Thank you to both replies so far to my post.

I wanted to note that when I say the detector is chirping, I mean a loud, abrupt beep. This is not a sweet chirp that a bird might make or even a bad bearing on a mechanical system. This is the kind of beep that is shrill and loud that smoke detectors emit to wake you up. But instead of a continuous "beep, beep, beep, beep" that you get when there is smoke detected, it's just a single "beep," then silence for 10 to 15 seconds, then another "beep." This is a beep that can be heard all over the house and is loud enough that it has awakend us in the middle of the night.

It is similar to the kind of periodic beep you hear when the battery is dying in the detector. But, as I explained in my original post, we know it is not the battery.

We are going to make another run through the attic to check for a smoke detector up there, but we've never seen one.

We have no mechanicals up there either except for a radon system fan which is at the other end of the house, not right above where the smoke detector is located. Also, if the radon fan begins to fail even a little bit, its performance gauge drops and the performance gauge is right on target so the fan is operating normally.

Next time the beep sounds, we'll go for the breaker first to see if it stops the beep. If it doesn't we'll know it is coming from something else other than the smoke detector system.

Thanks all.


09:03AM | 11/08/07
Member Since: 11/07/07
1 lifetime posts
We are having the identical problem in our house in the same location and did the same trying to fix it(new battery, new smoke detector one with hard wiring one with battery alone).

No effect.

I guess it is temperature related. When the temp drops at night the battery voltage drops and the electronics may pick up on it.

We are going to put the battery operated one in the fridge tonight to check.

Maybe a call to the manufacturer is i order.


07:06PM | 06/30/08
Member Since: 06/29/08
1 lifetime posts
Has anyone come up with an answer to this problem? My grandson has a almost new house and has the same problem.


02:24AM | 01/15/09
Member Since: 01/14/09
1 lifetime posts
We have three hard-wired Firex smoke detectors with battery back-up. One of them is chirping/beeping at random and at odd hours (often at 4am). We removed them all and took the batteries out and the sound still seems like it is coming from the ceiling. There is no attic above us, just another condo. Any advice welcome!

Tom O

03:39AM | 01/15/09
Member Since: 09/17/02
476 lifetime posts
Since you mentioed the brand name, try this site by Firex

Fo anyone else with this problem, try doing a search for the manufacturer & then visit their site.


06:39AM | 08/23/09
Member Since: 08/22/09
1 lifetime posts
We are having the same problem and are desperate for a solution. I, also, thought that maybe it had to do with temperature. It has been very humid for weeks so maybe it is more to do with moisture then the actual temperture. I will keep checking the sight for ideas and advice. Thanks and good luck to all!


04:33AM | 02/10/10
Member Since: 02/09/10
2 lifetime posts
Spooky how similar my issue is. One smoke detector chirping LOUDLY in the wee hours of the morning on the second story. Have contacted the contractor that installed our security system to see if they have any answers. Will post here if they have any useful guidance.


07:47PM | 04/25/10
Member Since: 04/24/10
1 lifetime posts
The beep is not coming from the disconnected harness , and certainly not from the exposed wires . It is likely a detector elsewhere or a different electronic device; those tones can bounce around the house . Make sure you haven't overlooked a detector somewhere.

Disconnect all detectors and remove the batteries . Simply removing the battery does you no good; it's the same as a dead battery . That is actually a very common mistake .

While you have the alarms removed, you might as well take some compressed air to clean them . Place the alarms somewhere out of hearing range, and hunt down any other beeps.

Some brands tend to have this problem.

Especially in the morning, when the moisture begins to condensate inside our homes . It is usually the coolest time of the day isn't it? A different brand and model does not seem to have this problem so much.


03:55AM | 04/26/10
Member Since: 02/09/10
2 lifetime posts
Turns out my situation was much simpler than I thought, and most of the nightmares listed here. Replacing the back-up battery resolved my issues. I also followed the step-by step posted at

Good luck.


10:45AM | 11/26/10
Member Since: 11/25/10
2 lifetime posts
I have a 3 year old home. The house has seven (7) smoke detectors, four (4) CO detectors, and, in the garage, two (2) heat detectors. All of the units have hard-wired power with battery (9V) back-up, all connected in a single network. The chirping happened about a year ago. I replaced all 13 batteries, tested every unit successfully (when you press a unit's test button, it sounds its own alarm first, then echos the alarm in all other units, then repeats this process, then re-sets. Then every 35-45 seconds (timed check occurred usually every 44 seconds, though sometimes as short an interval as 35 seconds or as long as 45 seconds), one of the units, a unit in an open area between upstairs bedrooms, chirps once. A repeat of the four upstairs alarm units resulted in a more than five (5) minute cessation of the chirping routine. So, I thought the insanity generator had ceased. Not so. It resumed its chirping in 35-45 second intervals. A re-test of EVERY unit proved every unit functions properly, has a connection to the network and the power source, etc. EVERY unit has a brand new 9V battery. Every unit has the battery properly installed (a battery installed backwards results in a shrill alarm immediately - I tested that concept). BRK electronics makes all three (3) types of the alarms in this home network. All 13 units have no dust or cobwebs. Bottom line: ALL the units and the network pass every test any expert or commentator online has mentioned. With so many online entries mentioning that their home smoke/CO/heat sensors/alarms chirp falsely at frequent and random times, it seems that until the home alarm industry can solve this problem, the US citizens will likely die from insanity or suicide before ever facing the risk of smoke or CO. I recommend immediate removal of ALL home smoke/CO/heat sensors/alarms until the industry clearly proves, beyond a doubt that every unit they offer for sale works properly, sells at an economical price, has a simple bypass for a single defective unit (if it decides to start waking the household with a false alarm or battery replacement chirp in the middle of the night), that has a simple (no glue, no more than two screws, a standard plug/pigtail wire connector, etc.) replacement process, and ALL manufacturers follow a STANDARD INSTALLATION PROCESS and STANDARD BATTERY REPLACEMENT PROCESS. Annual (or semi-annual) battery replacement should take no longer than five (5) seconds per unit. Current replacement times, with non-standard battery replacement (ALL from the SAME MANUFACTURER!) from unit to unit, with no clear battery polarity (+/-) indicators -- some have a swing-out compartment, some have a slide-out battery compartment, some have a battery wire harness, some require full cover removal, some require partial cover removal, some have a clip-off battery cover, some have one screw battery covers, some have two or four screw battery covers, some have phillips head screws, some have slot-head screws, all take 1-2 minutes (minimum) per unit for battery replacement. We want the detectors/alarms for the safety of our families, not to support the profit margins of the alarm companies.


08:20PM | 12/28/12
Some of these issues are due to ghosts visiting/passing through. Ghosts, as in apparitions. I know it sounds bogus, but believe me...


05:02AM | 01/20/13
Member Since: 01/20/13
2 lifetime posts
Same problem. Since it tends to happen in the middle of the night and I didn't want to go into the cold garage to break the circuit and change the battery (hardwired), I went to the website recommended in an earlier post and read... but the key thing I noted was RESET the alarm (red button for at least 15 seconds) and CLEAN the sensor...

I held the reset button for 30 seconds, and not wanting to vacuum at 2 am... I stood on my tiptoes on the chair, BLEW on the sensor area a few times...and SILENCE. Thank the Lord.

I'll change the battery in the morning--and reset it properly.


Answer: The smoke alarm will chirp at a regular interval, about once every minute, when the battery is weak and needs to be replaced. On units with the Visible Low Battery Indicator feature, the red LED will blink approximately 4 times a minute. Replace with a fresh 9 Volt battery. FireX Alarms are certified to be used with the following models of batteries: Eveready 216, 522, 1222, Duracell MN 1604 or Ultralife U9VL-J. Do not use any type of rechargeable battery. Once the battery is replaced, the beeping or chirping should stop. If the unit chirps at seemingly random times or at random intervals after replacing the battery, check for the following conditions:

1) The battery may be loose, or improperly installed.

Make sure the battery is fresh, and that it is snapped in all the way so it cannot be shaken loose. It’s possible that battery connections may not be making good contact with the battery. Disconnecting and re-connecting the battery once or twice will likely fix this condition. On units with a front-load battery, be sure that the battery compartment door is closed completely.

2) The smoke alarm cover may be dirty.

Dust and insects can collect in the sensing chamber of the alarm. An accumulation of dust in the sensing chamber can cause the unit to chirp. It is good practice to clean the smoke alarm when you change the battery.

Cleaning smoke alarms:

Remove the alarm from the wall or ceiling and hold the unit on its side. There is a gap between the front cover and the back plate. Take a vacuum cleaner with a crevice tool and clean all around the gap area. Pay most attention to the sensor, which you will see in the gap area. The sensor looks like a small tin can with slots in it.

3) Reset the alarm.

Most current model smoke alarms have a processor that retains certain error conditions, such as a weak battery. The error condition should reset when the battery is replaced but sometimes it does not and must be manually reset to clear the error.

To reset an AC unit with a battery backup:

Turn off the power to the smoke alarm at the circuit breaker. Remove the smoke alarm from the mounting bracket and disconnect the power. Remove the battery. Press and hold the test button for at least 15 seconds. The unit may chirp or alarm for a few seconds before going silent. Reconnect the power and reinstall the battery. The unit will chirp once when the power is restored and should not chirp afterwards."


04:33PM | 02/17/13
I have 4 electric smoke detectors that are beeping loudly in the middle of the night for a few beeps. I'm assuming that I need to replace them, but I can't find the brand name anywhere on the case. It just says they are electric with no battery back-up. I bought this townhouse a little over a year ago and the previous owners left me lots of manuals but not the manual for these smoke detectors. Where do I find the brand name?


07:41PM | 02/27/13
we have the BRK 2002RAC. today all detectors went off and would not stop. there was no smoke anywhere..or any type of heat. ist issue we have ever had with them. I replace batteries every year so its not that. I tried to plug one back in..but smae thing. any suggestions on what the problem could be?


07:08AM | 03/21/13
Same issue here, detectors going off in the middle of the night for no reason. Need to find the manufacturer after taking one down...


07:32AM | 03/21/13
I have the same problem as the original poster. I unplugged the smoke detector and there is still a beeping coming from the ceiling. I've replaced all batteries, I've replaced the beeping detector and still it beeps. I guess I will check the attic to see if there is a detector up there.


01:21PM | 03/29/13
We are currently having the same issue as the original poster as well... now the chirping is every three hours like clockwork and lasts for half and hour. Driving us crazy. The alarm that is still chirping is not even attached to the wall anymore, its as if the wires are chirping! Not possible it seems but that's whats happening...


04:27PM | 04/11/13
MSOMAHA, did you figure out the source of the annoying chirping yet? Did you try shutting off the power to see if it continued? I agree with the other poster, there has to be another source emitting that beeping sound. Another detector, or anything that may beep when the battery is low. My grandmother had a similar problem once and we searched her home high and low several times trying to find out what was beeping once about every five minutes. I finally opened a kitchen drawer and found her old cellphone there which she had never turned off. It was beeping because of the low battery. We couldn't believe it. Good luck!


04:28AM | 05/15/13
Im having this issue with a battery operated detector. Replaced it with a new unit and the new one is chirping three times once every half hour in the middle of the night. How can it be happening with a new unit with new batteries and why only when i am sleeping?


02:51PM | 05/16/13
i am having same issue. i took the detector away and put it in the garage when it was originally connected in the hallway of our living room. STILL BEEPS! there is no smoke detector and Fn thing still beeps somewhere up in the ceiling. its very annoying.


01:46PM | 05/29/13
Ok I have the same issue in the open hallway near the back door. I have determined that it is temperature related. If I leave the heating on then the chirping stops or during the summer if we have a colder night the chirping starts up again. I guess this detector is more sensitive than most( poor thing) and its position also has an effect.

Good luck.


09:32AM | 06/02/13
Same issues with chirping Firex alarms. It's been going on for 8 years in our vacation/rental home. I finally put in wireless detectors that are connected to our alarm monitoring. One by one, I've disconnected and removed batteries from the firex models. I did the last 4 today after one went off and I couldn't get it to stop. But after I have disconnected them all and removed batteries, one keeps chirping?? I ant figure out how ? Or how to get it to stop


05:49AM | 06/04/13
omg its happening here too! The hard wired one in the master bedroom, no less. I also think it is temp related, as ours does it during the night when it's cooler. If I turn off the air conditioning it seems to stop after awhile, once the temp comes up a bit. I'm ready to take a sledge hammer to the thing, and sleep has become a luxury.


03:29AM | 06/19/13
I have a hardwired system. The one in the bedroom started chirping every 40 seconds. There are 4 detectors upstairs and one in the downstairs hall. Green lights were blinking on all. I replaced all batteries and the master bedroom one still chirps. Green lights not blinking any more. I removed it from the ceiling and turned the circuit breaker off. It still chirps. The fire dept said they have come across similar situations. I am calling an electrician in the morning. Will likely have hardwired system removed and go to strictly battery ones where I can at least throw out one if it becomes defective.


01:51PM | 07/06/13
I have the full alarm going off at night! We just rented a 10-year-old home a month ago. Everything was fine until 4 nights ago. For the last 4 nights, all 6 of the hardwired smoke alarms (First Alert) have gone off. It lasts anywhere from 3 seconds to 15 minutes, and it occurs between 2-6AM. Sometimes the windows are open, sometimes not. To make the issue more strange, our neighbors across the street had their alarm go off this morning at 5AM. As they are gone for the holiday weekend, it lasted 4 hours. We are exhausted! Batteries have been been changed, detectors vacuumed. What the heck???


04:53AM | 07/09/13
We have a 15 year old home we just moved into & we r having the same problem. it's 3:50am and we are wide awake! Any suggestions are appreciated. thanks


07:26AM | 07/11/13
Great. I have the 45 second chirp issue in the middle of the night. I search the Internet and wind up here, where I discover you all have the same problem with no solutions. 13 year old home. Master bedroom issue only. New batt twice over the last week or so didn't matter. I'm not about to break out the vac, a ladder, at this hour. It's probably not the issue anyway.
Just venting here I guess cause I sure ain't sleepin'. Hammer in the morning.


07:51AM | 07/11/13
I found the solution. Since I could handle it anymore, I got out the ladder, pulled the batt, twisted the case and pulled it down. Nice Ez connector to separate from house wiring. Pulled the whole detector off. It's quite now. Goodnight.


08:38AM | 07/16/13
Make sure all the brands of smoked detectors match throughout the house.


04:17PM | 07/17/13
We are having the same chirping every 45 sec! I pulled firex smoke detector off and took it to him depot and bought a new one with battery backup this time. Unfortunately we still have the same chirping going on! Even when I removed the detector there is in the wires or something. Has anyone found a solution yet?


01:45PM | 07/20/13
Turns out for us, it was our CO2 monitor - which was located close to the hard-wired smoke detector. We thought the chirping was from the smoke detector, but instead, from the CO2. It had an ERR reading on it - we tried to spray the dust out - but the Error reading and chirping continued. We removed the CO2 monitor and will replace with a new one. Chirping stopped.


09:27AM | 07/22/13
Wow! Same with us! It turned out to be the CO2 monitor located near the smoke detector! So glad the chirping has stopped!!


01:21AM | 07/25/13
Have you checked your detector for spiders or other insects? My smoke detector has gone off (3 beeps at a time) a few times tonight and when I ran a vacuum over it a new friend came out to say hi. My wife didnt find him to be too friendly so I killed it. The detector hasnt gone off since.


05:33PM | 07/25/13
We have had 1 of our 6 hard-wired smoke detectors beeping/chirping at random times, night and day for 2 years. We go for long stretches where it's OK and then we have 3-4 days of hell. We vacuum, replace batteries, do all of the things all of you are doing. I've just spent the entire day listening to it every 4-5 minutes, and I just went up and took it down from the ceiling. The beeping continued from the gaping hole with 3 wires dangling!!! There are lot's of complaints here, but not many answers!


11:24PM | 07/27/13
We are having the same issue. Definitely coming from smoke detector and only beeps at night when temperature inside the house drops below 70 degrees. Help .


11:08PM | 07/28/13
I am having a similar issue. All new FirstAlert hardwired installed throughout house 6 months ago. Combos in halls are fine, but the smoke ones in the bedrooms (4) all take turns randomly making 3 fast beeps. Sometimes its one room then I dont notice it for a few days. Sometimes another room might do it twice in 20 min. Other times its one room every 3 hours or so. More at night than day, but sometimes in the day. They have done this since the day they were installed.


01:06AM | 08/11/13
I thought that my hard wired smoke detector was beeping from within the ceiling as well as some of the others who have posted on here . It was in fact one of the other battery operated ones that are also in the home that was chirping. Check them all if you are having this issue ..maybe you will get lucky and it was a battery !


08:55PM | 08/13/13
All green lights are solid and on. New batteries throughout. Still chirping!!!!!


08:53AM | 08/21/13
Have you tried running a test? Mine would chirp after replacing the batteries if it hadn't been tested. Just hold down the yes button for about 9 seconds to rum through a few test cycles and you should be good to go.


09:20AM | 08/28/13
Hi all, I have been dealing with the same issue and have a possible cause. I recently changed all hard wired units in the second floor and chirping went away for about a month. Low and behold it happened again today. I came on the sight to find an answer but no one seams to have figured it out. I think I may have stumbled app on a cause. If anyone thinks this may be their cause please repost. Here goes. I have three bedroom with window air conditioners. Two of the rooms door was closed and nice and cool the third had the air turned off and was about 20 degrees hotter. Is it possible that the temp in the one room wasn't close to the other and cause it to alarm? anyone?


11:38AM | 09/02/13
I have several hard wired smoke detectors and once in a while, invariable in the middle of the night, ALL of the detectors start sounding (not brief "low battery" chirps) long undulating waves of high frequency tones. This goes on for 15 - 30 seconds and then stops only to do this a few more times before stopping completely. Usually this happens in the fall during humid weather when there may be thunderstorms in the region (not in the immediate area). My theory is that these detectors have the capacity to collectively sound when any one unit goes off (this is a good thing) but that some freak signal coming over the power wires is mimicking the "collective sound off" signal that the detectors use when there is a real fire.

This is a giant Pain in the a...


12:01PM | 09/04/13
We have the same problem. Removed the detector and the beeping continues to come from the ceiling. Battery replacement has no effect. How can the *ceiling* beep!??


04:26PM | 09/21/13
We have had the same problem with new hard wired detectors.Spoke with first alert and they had us reset all the detectors. This did not work. They had us reset them again. No luck. The company rep on the phone said it could be caused by having florecent lights in the house. We keep getting random 3 beeps in a row on different units all through the house. Why would a company make some detectors that can have a problem with different lighting options


05:20PM | 10/08/13
Hello. I have five hard-wired First Alert smoke/CO2 detectors in my house. They are fine through out the summer when the windows are closed. As soon as the weather permits, and I open the windows the beeping returns, but only at night. The first time it happened, I called my fire dept as it freaked me out. They said that they would be happy to come check it out, but it not an unknown problem. They stated that as the temperatures change, the ozone levels in the atmosphere change and can affect the detectors until the atmosphere stabilizes again... I don't know how true that is, but I do know that having dealt with this for four years, the problems stops after a night or two. (I know, it's annoying as heck until then.) I've just dealt with it.
This doesn't help those of you who have removed everything and still have the beeping. I'm sorry, but I can't help you there.


10:37PM | 10/11/13
Member Since: 10/11/13
1 lifetime posts
I've enjoyed a chirp sound every 45 seconds for the past twelve hours now. I replaced nine batteries today/tonight to no avail. The chirp does not seem to be emanating from the combo detectors but near by, in the ceiling in the hallway upstairs. We did turn the heat on today for the first time. Just can't understand what is making the chirp sound. Scoured the attic for a clue--can't even hear the chirp in the attic storage areas. Reset circuit breakers over and over. Purchased new detector to try that option--no joy. House is one year old. Anyone else with this 45 second interval eve figure it out? I'll be calling a electrician first thing in the morning and will post what he/she determines.


02:49AM | 10/13/13
Having the same issue here in AZ in October which started at 10:45 and is beeping every 45 seconds. Removed two hard wired FIREX smoke detectors that were confirmed beeping, and once one was removed, others started going off. Going to check the wiring in each one, clean all, replace all batteries, and see if the beep continues.


03:16PM | 10/23/13
Hi all,

I had the same exact problem as what you guys had. These are the things I did. We have 5 smoke detectors in our house and two CO detectors.

1. I removed each of the five smoke detectors first from the connections completely and removed the batteries. Then, press the test button in your smoke detector to remove any residue charges in the detector for 15 seconds. You can press the test button a couple of times if you want. Once you drain the detectors, you put the batteries back and then connect each of them with the wires in the wall. This should mostly fix the chirping sounds for the smoke detectors unless they are very old in which case you have to replace them.

2. Even after doing all this, I still had some annoying sounds coming from the wall. For a day, I did not know what the source was...But later I figured out that it was the CO detectors which were close the smoke detectors that was creating the problem. I did the same for the CO detectors also separately and put them back..Now, the sounds are all gone.


12:20AM | 11/02/13
our home built 1977 detecter chirps wheen lite switch on other side of wall is flipped on or off.might be same problem


11:40PM | 11/03/13
Member Since: 11/03/13
5 lifetime posts
Just a question for all with smoke detector problems, are your houses fairly new maybe 2 to 8 years old


04:09PM | 11/04/13
It's somewhat comforting to know we are not alone with this problem, but in the middle of the night it is small comfort! Having this same issue with our hard wired battery backup units off and on for years. We have no attic in our log house we built 16 years ago so we know where all the alarms are. During the night one starts intermittent chirping (we call it the warning shot) and then soon they're all going off like there's a fire. We now keep a 10' ladder on the loft to reach the one on the cathedral ceiling to save time removing batteries during the night. If one goes off they all need to be removed to stop the alarm--if we're lucky. We replace batteries at an alarming rate (if we were smart we'd buy stock in Eveready and Duracell), we've vacuumed the alarms, replaced units and a few months ago again replaced all 6 units in the house. We thought that fixed it...Last night it did it again. The batteries were last replaced 8/14/13 but we replaced them again. Nothing worked and the system is currently shut off. I've tried to find a pattern but other than during the night, there is nothing noticeable. But something "happens" before the first chirping starts because our 2 dogs go crazy trying to wake us up and when I wake up enough to holler at them the *&$# chirping starts! Every time--they seem to know it is going to happen in advance. Will check manufacturer on our units and continue watching this site for answers.
Help! this is making us all crazy!


04:03AM | 11/05/13
Just went through this. Like others, it turned out to be CO monitor, which wasn't even that close to smoke detector. But high frequency sounds are notoriously difficult for the human brain to localize, and combined with hardwood floors for sounds to bounce off, it was impossible to tell by listening. Please please check your CO monitor if you have relentless beeping, even if you swear it couldn't be....


02:47PM | 11/09/13
The same thing just happened at our house. It was the CO monitor. Both my husband and I swore the ceiling was chirping after we removed the smoke detector, changed the battery, etc. We had to move the co detector to another room to discover that it was actually that and not the smoke alarm. We were on the verge of replacing all the smoke detectors in the house. I, like previous posters, urge you to check your CO monitor.


09:07AM | 11/10/13
Member Since: 11/10/13
1 lifetime posts
all of my first alert smoke alarms are chirping --they take turns--they are hard wired-- i have replaced the batteries--how do i fix this-- seems to happen in the middle of the night when everyone is sleeping


05:56AM | 11/25/13
Was irritated that some replies kept mentioning carbon monoxide detector. I could swear I knew exactly which smoke detector was affected. But just went back up the the master bedroom to check and my carbon dioxide detector was showing low battery/error. Right before I pulled it out of the wall, it beeped it's excruciating beep!

I think the sound of the beep is sooooo loud, it bounces off walls and makes you believe it's coming from another source. My house is quiet now and I can up from the basement!!


06:35AM | 11/27/13
I did the following to resolve this problem:

1) Take down all the smoke detectors. IF you have a CO monitor also hard wired, take it down as well.

2) For each detector, open the battery compartment so that there is no power to the detector. Hold down the test button until all beeping stops to drain the capacitor. The detectors usually have a capacitor that holds some charge even after disconnected from power and battery.

3) Close the battery compartment so that the detector is running on battery alone. If it starts to chirp, repeat with a new battery. If it chirps with a new, good battery, try blowing dust out of the detector and repeating. If it still chirps, get a new detector.

4) Once all detectors are working on battery power, connect them to power one by one. If the detector starts to chirp, then try a different detector in that location. If both chirp you probably have a wiring problem or connector issue at that location. If one chirps but the other does not, you probably have a wiring or connector problem on the chirping detector.

I hope this helps.

Most of this came from First Alert customer support. They were very helpful.


06:31PM | 11/29/13
It was the freaking CO monitor for me as well!!
After replacing the battery the beep stops! Thanks for everyone here.


11:25PM | 12/05/13
warm it up it worked for me


01:14AM | 12/09/13
I swear I was going insane, after removing the battery & smoke detector, and STILL hearing chirping "coming out of the wall" or the wires... but the solution was the same as many mentioned above. My wife had unplugged a CO2 detector that had been lying on the floor (under its electrical socket) for months, draining it's batteries, until it's low battery chirp started intermittently going off every minute... sounding EXACTLY like our smoke detector. Like others mentioned, my hears couldn't localize the frequency, so I thought I heard it coming out of the empty space where the smoke detector was hard-wired. CHECK YOUR CO2 DETECTOR in the room!


11:27AM | 12/22/13
We had the same noises - it drove us crazy. We replaced all the batteries in the smoke detectors - carbon monoxide and even the thermostat. It still kept up with that damn noise. We heard noises coming from the attic. My son went into the attic and found another smoke detector in the attic. Changed it and end of noise. Unbelievable!!


11:31AM | 12/22/13
We had the same noises - it drove us crazy. We replaced all the batteries in the smoke detectors - carbon monoxide and even the thermostat. It still kept up with that damn noise. We heard noises coming from the attic. My son went into the attic and found another smoke detector in the attic. Changed it and end of noise. Unbelievable!!


11:35PM | 12/30/13
Same exact problem. Wires in ceiling seemed to be chirping! Drove us crazy. Finally DID find the problem. In the same room where the chirping was coming from -- and behind a couch against a wall -- was a CO detector. Just a battery type CO detector. Pulled the battery on it and no more chirping! I too thought it was the wires in the ceiling box chirping. Of course that's impossible and thankfully it is -- it was the separate, stand-alone CO detector with a bad battery playing ventriloquist! And doing a very good job of it!! Good luck.


12:52AM | 02/11/14
I had the same issue and forgot that I had a separate CO detector that plugs into a wall outlet. The CO detector's 9 volt battery needed to be replaced and produced a loud reminder chirp every ~45 seconds. After replacing the battery, the chirp no longer sounded.


03:29PM | 02/11/14
Try taking them down and blowing them out with a can of compressed air. Many times during construction they get dust in them and over time they build up dust also which triggers the chirpping. It worked for me. I thought that I was going to have to replace mine in a 5 year old house.


07:21PM | 02/16/14
Just finished with this issue.


1. Clean the dust out of them with a can of compressed air and/or a vacuum cleaner. Feel free to remove the detector from the ceiling but do NOT open the detector itself. Get as much dust, dirt, and spider webs out as possible.

2. If #1 fails, and the smoke detector(s) are more than 10 years old on average they may need to be replaced.

3. If you have removed all the smoke detectors and still hear chirping, check for other smoke detectors and CO2 detectors. A general rule of thumb is each level of your house should have 1 smoke detector. C02 detectors should be located outside the furnace room in your basement and outside the bedrooms. If you find any of these disconect the power and/or batteries to take care of the chirping.

Hope this helps! I was driven crazy at 3 A.M. 2 times this weekend before finding the last of them. :)


01:28PM | 03/09/14
I am so relieved to not be alone in disgust over a chirping hard-wired smoke alarm! I have a highly fearful dog who comes unglued at the midnight detector malfunctions -so at 2am one particularly rough night, I ripped the chirpers off their mounts, and took a hammer to them in the garage. They shattered nicely and stopped chirping. I then brought my dog into the garage to inspect my handiwork, and he was most appreciative. We all got some sleep. My vote on causes is temperature change, plus old devices.


11:25PM | 03/15/14
Yes it was the co detector for me also.Now we can sleep.Thanks for all the great advise.


01:51PM | 04/12/14
We suffer with the wired smoke alarm chirping disaster from time to time. Today I would have SWORN it was the smoke alarm again and the sound was moving from unit to unit. My hubby wasn't here to help so I went to Google in desperation. I saw this thread and it made me check the CO2 unit. It was the 100% the culprit. The sound it makes can absolutely trick your ears into believing it's coming from somewhere else.

Thanks for the advise, it worked for me. I wouldn't have thought to check the CO2 unit for a long time, if ever.


08:13AM | 04/23/14
We had the '3 chirps' problem happen: 3 chirps, pause, 3 chirps, then nothing. It was fine for a couple of months, then it happened again. And again. As other folks in this thread indicated, it was the CO2 detector.

I looked up the First Alert manual to see what the chirp code meant. Just once/minute would be low battery; 3 chirps is the alarm indication, but would be continuous; 3 chirps, pause, 3 chirps is the test mode. Of course, no one was testing the CO2 alarm, so it was a puzzle.

I unscrewed the alarm to inspect it. It was clean, the LED was green, etc. Then, as I went to put it back, I noticed some movement: the black wire on the alarm was loose from its wire nut. If it was twisted just right, it would lose connection with the house power. So much for using an electrician!

If this is the problem for you: with power off, unscrew the wire nut, straighten out the alarm's wire, stick the alarm wire into the wire nut first, follow with the copper from the house, then twist to make it snug. Over-tightening can cause it to ride up and slip out. (don't forget to turn the power to the detectors on again)

I haven't had the problem again. As one writer indicated - it may have been related to a temperature change: after a few warm days, it got cool, and the metal may have contracted just enough to lose contact with the house power, and then recontact. The manual doesn't mention it, but it may be that the right pattern of random power connections gets interpreted by the alarm as a test. (like the old rotary phones: you could click the receiver to imitate the clicks for each number)


10:16PM | 04/28/14
Thanks so much!! It turns out to be our CO2 monitor also. Whew! So happy to find this site.


07:08AM | 05/12/14
I had the same problem. Changed the battery, changed the battery to every smoke detector in the house. Still the sound did not stop, and sounded like it came from the wiring in the ceiling. We went in the attic, to see if there was a 'lost' detector in the attic. We turned off the power to the house, still the chirping did not stop. After reading all of your posted, seems like a common suggestion was to check the carbon monoxide detectors. I had earlier in the day checked the one in basement. But remembered that there was a 'plug in' carbon monoxide detector sitting on the floor near the chirping. It was unplugged. I did not think it had batteries in it. but thought I should double check. I had tried everything else... Sure enough.. that was the source. My husband & I both thought the sound was coming from the ceiling wiring. Now we can rest...


05:57PM | 05/31/14
Member Since: 05/31/14
1 lifetime posts
I had the same issue as many have stated above. I changed all batteries, changed all smoke detectors, unplugged all smoke detectors only to find out....that it was my plug in carbon monoxide detector. When the batteries on the plug in carbon monoxide detectors go low, it makes the same chirp as the smoke detector. Because it is plugged into the wall, it sounds like the chirp is coming from everywhere in the house but the wall detector. I thought it was in ceiling, different rooms, as many have reported here. Very frustrating but the good news, i guess, is that I have all new smoke detectors that has not been replaced in 14 years. My house was built in 2000. Good luck and I hope this helps.


08:26PM | 06/18/14
Didn't help. Still chirping. Installed new ones and replaced all batteries and did step by step still going


09:30AM | 06/21/14
i reset the smoke detector after changing the battery and it started chirping again after 20 hours. what next ?


09:30AM | 06/21/14
i reset the smoke detector after changing the battery and it started chirping again after 20 hours. what next ?


07:45PM | 06/25/14
Try removing the battery, THEN holding down the reset button. I know this sounds silly, but it worked on my mother in laws detectors. There must be a capacitor in there or something that you discharge with the reset button.
I unplugged it, removed the battery and held the reset until the detector sounded a short beep, longer than the dying battery chirp, but pretty short. That seemed to do the trick.


05:17PM | 07/14/14
After a lengthy power outage, during which the smoke detectors continually kept beeping, the hardwired smoke detectors continued to beep when the power was restored. I dragged out the ladder and hit the reset button on everyone of them. THEY KEPT BEEPING. I was about to get out a gun and just shoot all of them, but then I remembered I do not own a firearm! So, in order to save my sanity, I started researching non violent solutions to reset the smoke detectors on the internet. Thank goodness for this website. It was the CO2 monitors! Like many other comments, I swear the sound was coming from the ceiling.


12:41AM | 07/18/14
OMG....we just figured out it was our CO2 sensor, the darn thing sounds exactly like the smoke detector. Now, unfortunately, we need to get the ladder back out and re-hook up all of our smoke detectors since we disconnected them. But alas....the beeping has stopped!


06:54AM | 07/18/14


10:01PM | 08/04/14
I also need help! I'm not familiar with the First Alert system, but one of the detectors is chirping and I can't get it out of the ceiling. I need help! no one's around at this time of night to come over and disengage this thing!


12:28AM | 08/18/14
If you can locate the smoke detector that is making the chirp remove it from the wall (disconnect the plug) and remove the battery. While it is disconnected press the test button. You will get a weak test sound. Keep holding the button until the sound dies away completely draining the energy stored in the system. Now hook everything back up, install the battery and press the test button. Your chirps should be gone!


07:59AM | 08/19/14
My hard wired smoke detector began to beep but it doesn't appear to have a battery backup. This is 2014 and the cover of the detector says to replace in 2004. Do I have to replace the whole thing?


05:16PM | 08/27/14
For the second time this week, our First Alert smoke/carbon monoxide detector has done the following:

one chirp
three long beeps
three long beeps
four short chirps
four short chirps
one chirp

The first time it did this, we replaced the batteries (this was a few days ago). Then it just happened again this morning. I'm assuming it's some sort of malfunction. It seems like it's making all Has this happened to anyone else?


09:10PM | 09/01/14
I'm having the same issue. I've flipped the breaker off and unhooked them. STILL CHIRPING about every minute.


11:11PM | 09/17/14
Having the same problem. Cleaned all of them removed the batteries and removed them from the ceiling. Then put them all back in and a hour later one starts beeping then an hour later the beep moved to another area of the house. Please help going crazy along with my two dogs


06:57AM | 09/18/14
People you need to understand the life of a smoke detector is 10 years (or less for you smokers) and should be replaced after that amount of time. Quit screwing around.


05:06PM | 09/21/14
I have three smoke alarms in my house (First Alert). They are wired into the house AC, but have battery backup. They are also wired to communicate with each other. One, the one causing the noise, is also a CO detector. In the last few weeks one of them has started giving me a single beep (let's call that E) or a triple beep (let's call that S), in the middle of the night for no reason. E is a signal to replace the battery, per the manual, although it should be doing it every hour, in that case. At first, I dutifully changed the battery (three nights in a row). S means smoke, but in that case it would be louder & continue until manually reset. There is no smoke. In fact, it DOES NOT go off when the neighbor's BBQ scent drifts through my house.

Finally called the electrician who installed them. The first time he came out, he said they were all old enough to be replaced & charged me a lot to do so. He's been out twice since, because the problem continued, always at night. The only thing he does is replace the offending unit (for free). There is no latch light on any of the three, so no clue which one started the fracas.

What gives!!??!! I'm losing sleep & the dogs are going nuts. Sometimes it triggers a dog fight.


11:24AM | 09/22/14
Ceiling that holds the wires for the detector have a speaker or amplifier in it that is allowing us to hear, But instead of a continuous ,that you get when there is smoke is all round. 


08:15PM | 10/05/14
Member Since: 10/05/14
1 lifetime posts
Oh my gosh - we lost power 3 days and the smoke detectors started going off. Got so frustrated that took them all down, and the chirping continued from what seemed the base of the two alarms in the hall. I looked in the attic, turned breakers on/off and looked in the electrical box of the mounting base but now speakers or componenets that would chirp. Torture enough not having any power, and then to hear loud chirping every 30 SECONDS day and night! At wits end and reading this thread it clicked, we had gotten a carbon monoxide detector as a gift that plugs into wall and we put it behind a small table in the hall, the chirping made the smoke alarms go off, and when i took the alarms off it echoed so made it sound like the mountings in ceiling were chirping...TOOK IF OFF THE WALL, CHANGED LOW BATTERY AND NO MORE CHIRPING!!!!!!!!


08:55AM | 10/07/14
We don't have a CO detector, but our smoke detector on the cathedral ceiling started randomly beeping at weird hours (specifically at night). After changing the battery and testing it, it seemingly stopped...until the next day. In a fit of frustration I ripped it off the wall, removed the battery, and stored it in a distant room. Well a week later the beeping returned and I thought I was going nuts. It started as one beep once a week or so, now it beeps randomly two or three times on one day a week or every other week. It's like its coming out of the wall! All other smoke detectors are fine and have a green light. The sound is definitely coming from the wall. I have no idea what to do and my dog is going absolutely mad at the sound. There is no CO monitor installed anywhere in my house (if there was, no one ever told me about it). How is beeping from the wall where the detector was even possible?? Or maybe I am just going crazy...


12:41PM | 10/13/14
Thank you to everyone who posts information because it can be extremely helpful to others!! I thought my smoke detector needed a new battery because it started the high pitched chirping. I tried 2 new batteries and resetting etc...and the chirping continued. Luckily, I saw the post to check my carbon monoxide detector which is nearby. I put new batteries in that and now all is quiet!! Thank you again!!!

leo w

01:14PM | 10/13/14
Member Since: 10/13/14
1 lifetime posts
I changed all my smoke alarms last year. I noticed that all the circuit boards had small burn marks on them. Yesterday all the alarms went off at 3 in the morning. I took all the smoke detectors apart and noticed the same thing happened again. Tested all the lines and had 117+- volts. I had no loose connections. The detectors are hard wired into my fuse panel. Any ideas whats causing this? I have to buy 7 new detectors and afraid it will happen again. Any advice?


05:34PM | 10/24/14


07:13PM | 10/24/14
After disconnecting the smoke detector from the battery and mains power, ready to pull my hair out from the incessant beeping:
Me: "Are you SURE you don't have a carbon monoxide detector in this room? They beep when they run out of battery power."
Girlfriend: "YES, I'm SURE I don't!!"
Me: "Are you sure you're sure?"
Girlfriend: "YES, I told you YES!!"
Me: "OK, I'll go check the other rooms."

5 min later...
Girlfriend: "Oh, oops... there was a carbon monoxide detecter plugged in behind a box. It needs new batteries."



05:46PM | 11/02/14
The electrician who did our remodel wired all the detectors to a common ground. Turned out to be same ground as the refrigerator. At night when the electric current varies a little because of the power grid and our fridge would kick in at 2am then BEEEEEP. Took us two years before another electrician told us what's happening. We disconnected the alarms from the house current and just use the batteries, like in the old days.


10:31AM | 11/04/14
Same problem here, how do we fix it??????


11:35PM | 12/05/14
I found the issue for the chirping coming from the ceiling!!! First, let me say that I have no electrical experience at all, I am a single female living with my daughter so I was hoping I would not have to toy around with the wires in the ceiling to kill the chirping. I did, like the rest of you, replaced the battery...twice!!! Held the button down to drain the "juice" that might be left in the system, but like you all, the noise was coming from the ceiling. I finally decided to check the darn plug in Carbon Monoxide plugged to the hallway outlet and low and behold, the damn thing had an ERR message. I yanked it from the wall and removed the battery.....guess what????? Silence, Halleluiah. Oh I had also tried the shutting off the circuit breakers, so as you can see I tried everything. LOL Please try it:) Veronica


02:48AM | 01/03/15
We, too, have a hard-wired-with-9-volt-back-up smoke detector system. Less than a year ago, we were advised to change out one of them to a carbon monoxide/smoke detector to bring the home to current code. Though we have had similar issues in the past, this "chirping in the ceiling" is a first.

All of our detectors have new batteries as of 4 hours ago.

Still, the chirping continued. We removed the batteries, "drained" the existing charge per the internets, and still the chirping continued.

We removed the detectors, and removed the batteries. There isn't a single detector in it's proper place right now.

Still, the chirping continued. We got into each box, untwisted the wires, and capped them. There are no electrical connections, now, and the wires are hanging from the ceilings in each room.

Still, the chirping continued. From the ceiling. Where there is no detector.

(I know finding the source of the sound can be difficult, as the chirps seem to bounce from detector to detector/room to room, but as they're all in the kitchen and the sound is definitely in the hallway, we've been able to pin it down.)

So, then, it's getting late, and it's cold, but why not crawl into the attic? Moved all sorts of insulation 'round to see if there was something hidden up there. Short answer is no, there isn't.

HOW IS IT POSSIBLE that a chirp can come from the ceiling, where there is no electrical connection? It's not a CO detector, because the only one we have is sitting next to me with it's battery compartment open like a dead body that Dr. Mallard has examined.

We are clearly not alone in this, because so many have posted this problem, but nobody has found/shared a solution that isn't an "Oh, we forgot we had XXXX." Where is this noise coming from? How can there be chirping when there is no detector? Does it have to do with the hard-wiring? Some sort of circuit sensor is po'd because the circuit is incomplete with all the detectors removed? I even turned the heat on to see if the system wanted to be a toasty 70*, as it's a little chilly tonight. Nope! Arggghhh!


09:12AM | 01/03/15
We, too, have a hard-wired-with-9-volt-back-up smoke detector system. Less than a year ago, we were advised to change out one of them to a carbon monoxide/smoke detector to bring the home to current code. Though we have had similar issues in the past, this "chirping in the ceiling" is a first.

All of our detectors have new batteries as of 4 hours ago.

Still, the chirping continued. We removed the batteries, "drained" the existing charge per the internets, and still the chirping continued.

We removed the detectors, and removed the batteries. There isn't a single detector in it's proper place right now.

Still, the chirping continued. We got into each box, untwisted the wires, and capped them. There are no electrical connections, now, and the wires are hanging from the ceilings in each room.

Still, the chirping continued. From the ceiling. Where there is no detector.

(I know finding the source of the sound can be difficult, as the chirps seem to bounce from detector to detector/room to room, but as they're all in the kitchen and the sound is definitely in the hallway, we've been able to pin it down.)

So, then, it's getting late, and it's cold, but why not crawl into the attic? Moved all sorts of insulation 'round to see if there was something hidden up there. Short answer is no, there isn't.

HOW IS IT POSSIBLE that a chirp can come from the ceiling, where there is no electrical connection? It's not a CO detector, because the only one we have is sitting next to me with it's battery compartment open like a dead body that Dr. Mallard has examined.

We are clearly not alone in this, because so many have posted this problem, but nobody has found/shared a solution that isn't an "Oh, we forgot we had XXXX." Where is this noise coming from? How can there be chirping when there is no detector? Does it have to do with the hard-wiring? Some sort of circuit sensor is po'd because the circuit is incomplete with all the detectors removed? I even turned the heat on to see if the system wanted to be a toasty 70*, as it's a little chilly tonight. Nope! Arggghhh!


05:34PM | 01/08/15
I have no co monitor, nor are there batteries in my smoke alarms ... yet one is still going off ... any answers?


09:21PM | 01/25/15
Member Since: 01/25/15
1 lifetime posts
I've been having this annoying problem, too, and finally resorted to reading the Kidde troubleshooting page on their web site. It does say that a loose neutral wire (it's the white one) can emit a chirp even when no detector is attached. Hope the original post got their problem fixed already, as it's been a long time! Just thought I'd put this out there. Those people are not crazy!


11:26PM | 02/19/15
Same thing, I vaccuumed, I tripped the circuit breaker to reset the smoke detector, two new batteries, nothing. The CO monitor was unplugged when we painted and was chirping under my ladder. New battery, problem solved.


06:46AM | 02/23/15
Over the last couple of weeks, it seemed as if one of my hard-wired smoke detectors started chirping around 5.00 a.m. on some mornings every 45 seconds. A couple of mornings after I reset what I thought was the offending one, it stopped. This morning it happened again. I could not stop it. I replaced a couple of batteries, still no result. Then I read this article. I have a CO detector on top of the upstairs bathroom cupboard, near three smoke detectors and that was the problem. It seemed to "throw" its chirp voice around the house. Batteries replaced and blessed silence - maybe worth being up at 5.00 a.m.


07:42AM | 03/04/15
We were startled awake this morning by one, then two, then three thenf four of our hardwired units blaring (not beeping) They were all on one side of the house. By the time we all got up, and started gathering our things to get out and I got the garage door open they stopped. Hours later not even a peep. A little freaked out. Hit online and apparently it's a thing and no one has a solid answer but am still spooked.
Any advice welcomed.


10:00AM | 03/16/15
Hard wired smoke detector is chirping....what can I do.


12:29PM | 03/30/15
I too had a similar problem. Pulled all the detectors.. shut down the circuit etc etc. Still a beep from the basement area. Hidden behind a clothes rack,I found a red light on the Verizon Fios Optical box showing "low battery". Replaced it (12 v) and finally it has stopped. Had me going for a number of hours and complete consternation, but finally found the "fix" for my house at least. Good luck to all.


06:34PM | 04/24/15
Unbelievable. I thought everyone was crazy until I started seeing posts about CO monitors. And then the one post about their FiOs box. I replaced the battery twice in the smoke detector and that beep happened while I was up there. Not coming from the smoke detector after all. We have no CO monitor. So I looked at the Verizon box. Sure enough the "replace battery" light was on. We have Comcast now, so I simply unplugged it and removed the battery. Woot!!! Thank you to all the detectives who gave me ideas, especially the FiOs one!


11:06PM | 06/01/15
Thank you for mentioning the CO detector. Once that battery was changed the chirping stopped!


11:29PM | 06/05/15
All detectors went off 2 times at 11:00pm. Opened all upstairs doors of bedrooms and not going off after 25 minutes.


12:22AM | 06/08/15
Problem solved. I spent 6-7 hours trying to figure it out and reading every blog. I heard the sound coming from the ceiling and the wires when the detectors were siting on my table with no batteries in them. Most answers said CO detector nearby; but my 7 year old Florida home has no CO detector because we have no Gas to our homes. However, I remembered after much prayer that I had packed in a box 2 old CO detectors and 2 old smoke detectors from my midwest home 2 years ago. Behold, the 2 CO detectors in a closed box had a dying battery. The high pitch sound was echoing louder from the attic than it was coming from the actual unit when I pulled it out of the box. Very very strange but silence at last. Anyone reading this already knows the anguish this search causes, I was convinced that there was a detector in my attic under the insulation because I clearly heard it through the AC duct. So know that the beeping unit could be packed away and where you think you hear it is not necessarily the place it is coming from.


12:55PM | 06/26/15
If you haven't tried already.. reset your circuit breakers. Hard wired smoked detectors having their batteries changed is great, but the true power comes from the wires. Resetting your circuit breaker for the smoke detector should delete the error codes. Hope this helps someone :)


09:47AM | 06/29/15
I came here to find a solution to a mysteriously beeping smoke detector issue. I had the same problem that many of you had: replaced the battery, reset the detector, checked all of the other units...nothing. Many mentioned that the beeping was probably from a carbon monoxide detector. I replaced all of the batteries to those, but the problem was still not solved. I figured out that the problem was with our office smoke detector, which was beeping from the ceiling even when I removed the detector. Then, after hours of frustration, I glanced over to a shelf and saw our old plug in carbon monoxide detector from before we had everything hard wired two years ago. I took it outside & when it started beeping, I discovered that this was the problem! After removing the batteries, no more beeps. I had no idea that even a detector not in use could cause that beeping to happen!

Hope this might help someone!


03:32PM | 07/08/15
I had the same problem of all the alarms in the house going off over and over again for a few hours (not chirping, but fully sounding). And then as we were monkeying with things, we saw a tiny little spider crawl out of one. Unfortunately he crawled back in (setting that alarm off again, which set the rest off). So we had to remove that detector and now all the alarms have stopped. What a terrible design if a little bug can crawl in and set off alarms for hours and hours. Anyway, could be a bug.


08:13AM | 07/23/15
WE had a storm w/a lot of lightning and all of the hard wired smoke detectors in the house went off at once(total of 9).I replaced all battery's and alarms still go off.Is it something simply or involved


03:46PM | 07/25/15
I had exactly the same circumstance -- chirping hard-wired smoke alarm. Removed the detector and it seemed like the chirping was still coming from the ceiling. I checked my attic too -- nothing. Changed the batteries on every detector 4 times. Then I started reading further down in this string of responses. It never occurred to me it could be the CO2 detector, but that's exactly what is was. It was plugged into an outlet in the same hallway as the smoke detector I thought was chirping. I've gone for 3 days with very little sleep and even called the alarm company. To all of you who posted to check the CO2 detector -- THANK YOU, THANK YOU, THANK YOU! My dogs thank you too!!


03:38PM | 07/26/15
BV004802 you da bomb. It worked to remove the battery, hold the reset button for about 30 seconds and then reinsert the battery. It did the intermittent beep for a few more times, then stopped. THANK YOU!


03:42PM | 07/26/15
Okay, I spoke too soon BV004802. It's b-a-c-k. Fortunately an electrician is coming in the morning to do some work and I'll have him tackle it. If we can just keep our sanity in the meantime . . .


11:57PM | 07/28/15
Thank you for the CO2 monitor suggestion! God Bless you!


12:14PM | 07/31/15
I had very bad renters they stole all the fire detectors wired into the house... can I replace these units?


03:17PM | 07/31/15
We recommend Firex on our site to all of our buyers. It seems to solve the issue


12:31AM | 08/11/15
Try resetting the smoke detector on the unit itself after replacing the battery. Also, go to the fuse panel and turn off the fuse for the detector. It has several possible labels "alarm" and "smoke detector" it's usually a power surge that caused the initial problem.


09:53AM | 08/17/15
Thank you BV002660. Great information and your comments resolved my issue.


12:58PM | 08/29/15
I had taken all detectors down, reset them and reset the breaker but something was still beeping.

I found that the sound was not from the hardwired smoke detector but from the security system that was right by the smoke detector-both upstairs and downstairs. Luckily, I had remembered that it had a battery backup. The beeping it was a warning indicator (beep) for the alarm system battery backup.

I was just about ready to dig into the walls. LOL


06:15AM | 10/18/15
I have 8 smoke, 2 CO and 2 combination detectors in my house! 4 smoke are interconnected, 4 other smoke are interconnected, 2 CO are interconnected and 2 combination are interconnected. Imagine the confusion when one goes off!! I have no idea of its origin. Oh and my kitchen houses 1 of the smoke and 1 of the COs which of course go off whenever there's the slightest bit of smoke. So I unscrewed those, unplugged them from the hard wire, then screwed them back in so that they are stand alone. Have no idea if this is dangerous but at this point I really don't care.


11:23AM | 10/20/15
Member Since: 10/20/15
1 lifetime posts
i have a chirping sound coming from my hard wired smoke detectors in two rooms i checked the batteries which were good finally removed all detectors now chirping comes from the ceiling in the same rooms what could it be?


09:56PM | 10/25/15
Thanks to all of you who said it was your CO detector. It was the same for us. I nearly went insane trying to fix it, and I went through changing all my smoke detectors (anyway, they were 12 years old & needed it) - but the whole family remained in a tizzy because the infernal demon that sounded like it was living in our walls, kept chirping every 60 seconds or so. But when I read the posts about it maybe being the CO detector, I pulled it out of the wall and lo! Sweet, sweet silence. Now, sanity is returning, and I can rationalize again; and I see that the CO detector (like a smoke detector) needs new batteries now and again.

Once again, thanks to all the angels who posted here. You are the guardians of the soundness of our minds!!!

Paul in Bowmanville On, Canada


08:16PM | 11/03/15
Hard wired detector goes off for no reason in the middle of the night. Red light flashes every 3 to 4 minutes in the day, all day. What can about it


10:05PM | 11/11/15
LOL Same for me it was my Carbon monoxide alarm. 2 night without no sleep, changing batteries and bought another smoke alarm. LOL And found this!! thank you!!!!


02:23AM | 11/14/15
Our alarm is beeping three times intermittently and even with a new battery installed it will not stop. Happened once before and it was low battery. We just replaced and it keep chirping. Can't go to sleep! Anyone got ideas?


08:24PM | 11/30/15
Thank you all carbon monoxide answers. You saved my sanity! The dogs finally came out from under the bed too. I was sure it was the smoke alarms. Bought two new ones but chirp never stopped until I read the CO posts. Gracias.


02:19PM | 12/09/15
I had exactly the same thing happen. 3am the smoke detector in the living room started a loud chirp every minute or is hard wired and connected to many others throughout the house. None of the others were chirping. I thought it the wiring as tha
t happened one time, so i pulled it down and the wires looked fine. I did have this feeling that the sound was not really localized in the unit. after reading all these posts i realized i have a stand alone plugged in unit for carbon monoxide detection near the smoke is all dusty and dirty and i removed it from the plug and the horrible repeating alarm stopped. so it was never the smoke alarm. i would have never thought it was this unit with out reading all these posts, so thanks for saving my sanity.


05:16PM | 12/14/15
After trying everything and getting in an argument with many people that the beeping was coming from the ceiling with no smoke detector connected. I finally read one person's post where they discovered that their Verizon Fios box had a red light on it saying to change the battery and was beeping every 15 minutes. Well guess what so do I and the beep is coming from IT NOT THE CEILING! this box is just under my smoke detector so it was echoing. Problem solved! Boy am I embarrassed.


03:31AM | 12/16/15
I have 6 smoke detectors and 2 combination detectors and they are about 10 years old and need to be changed out. I ordered new ones online because they did not have them in the store and it has been almost 2 weeks and I still haven't gotten the new ones in. I turned off the power at the circuit breaker, took all of the detectors down and took out the batteries and every 8 hours or so there is still chirping for about 45 minutes. If I put the battery back in the one that sounds like it is chirping and push the test button, it will stop the chirping for anywhere from 6 to 14 hours, so it has to be coming from something that is hard wired into these units, doesnt it?I guess I will look in the attic again.


10:10AM | 12/30/15
Mine started going off intermittently around the same time frame with 3 consecutive beeps. There was a spider next to it. Got rid of spider and the beeps where gone. ... Great posts; thanks all!! BTW, mine is hardwired with battery backup, the unit was a few months old and the light was green.


06:34AM | 01/05/16
A few things you can do,

1. disconnect all alarms remove batteries. Hover any holes around alarm, hold down test button for 30 seconds until capacitors are discharged. Replace with new batteries, ensure correct polarity and hard wiring connector is clipped properly in.

2. After step one if still bleeping intermittently go around and press the test button on each for 5 seconds.

3.Still having problems, get a competent person to check the hard wiring at alarms and distribution board.

4.Replace alarms


12:14AM | 01/10/16
We also thought it this alarm was coming from our smoke detector. After replacing all the backup batteries, we discovered it was NOT our smoke detector. It was the carbon monoxide detector screaming that we needed to change the backup battery. Problem solved!


10:09PM | 01/14/16
We have 5 smoke detectors and have removed all put them outside and still the ceiling seems like it is chirping. We have gone to the article where the noise is muffled. We have shut of the main electric to the house still chirping. We have cut out holes in walls to see if rouge detector and nothing. Read that the white wire could emit a chirp but the power is off to detectors. Who can we call to help locate this chirp. No other co or smoke detectors in house. The sound is localized I one bedroom.


01:26PM | 01/21/16
Although it sounded like my two upstairs smoke alarms were chirping intermittently, the culprit was my First Alert carbon monoxide alarm needing new batteries. In troubleshooting I first removed batteries from all five smoke alarms. Still chirping so I shut off power via circuit breaker. Still chirping but this time I noticed the carbon monoxide alarm red light blinking. Note that the chirping sound still appeared to be alternately coming from the two smoke alarms. Thanks to all of the comments on this issue otherwise I would not have figured out solution to my problem.


10:02AM | 01/23/16
THANK YOU! It WAS the Carbon Monoxide Detector after all.


11:24AM | 02/03/16
Does anyone know if space heaters can cause photoelectric smoke detectors to sound? The middle of the night is when 8 units go off. About 6 nights now... we are all loosing sleep. Every detector has been replaced, all back-up batteries for all the units (which are all hard wired) have been replaced. The only way I can get them to be quiet is to disconnect them, when disconnected, on battery power only, they are all fine. ...Confused....


09:06PM | 02/09/16
We had this problem in a house and we finally found a carbon monoxide detector plugged into an electrical outlet. We removed it and the problem was solved. Hope this helps.


10:12PM | 03/02/16
Just read through this whole thread as the beeping is driving us bananas. Replaced all batteries. Reset all units. Checked all CO2 monitors. Similar to many people, it seemed like the beeping was coming from the ceiling after we had the detectors down and disconnected. I crawled all the way through the attic on my stomach in pajamas, looking for rogue smoke detectors and found nothing.

Ready for the answer?

A smoke detector in a closet under a pillow!!! When we re-wired in 2014, looks like this old unit (marked 2006) was taken down and shoved in the closet, only to be forgotten about.

Bless this thread for helping me keep the faith that there was another thing making the sound and we just hadn't found it yet.


05:58AM | 03/04/16
Last weekend, smoke alarms started chirping at 4am. Replaced all the batteries. Fine. This week, same thing but stopped when i clicked the heat up to 72. just now, again. Read on here about Co2. It is not hard wired but I took the battery out and it instantly stopped. Thanks! Stay tuned cause if it starts again I am jumping out the window.


10:48PM | 03/05/16
about two years ago I replaced all my hard wired smoke detectors and used lithium batteries. Everything was ok until now. I am back to having the same problem of the smoke detectors blasting in the evening and mostly in the middle of night. The electrican is telling me to change all the wiring going to smoke detectors, at Acosta if almost 3,000 dollars I question his suggestion. Then he suggested adding a surge protector to the house...another 550 dollars that I am questioning.


10:14PM | 04/12/16
We had the same problem once with all three smoke detectors in the house, and it didn't help even if we changed the batteries and blew off dust. But magic kicks in when we took the batteries out and shut off the power to the smoke detectors for a few minutes. Then turned on the power and then replaced the batteries. All quiet !!!

Try this, as the smoke detectors need to be turned off, like a computer, to correct the internal problems.


12:39PM | 04/30/16
my circuit breaker will not reset. I noticed this as I was fixing my door bell chime, which apparently is on the same circuit.


12:40PM | 04/30/16
my circuit breaker will not reset. I noticed this as I was fixing my door bell chime, which apparently is on the same circuit. Can the chime transformer just go bad, or is something wrong with a smoke detector?


02:41PM | 06/12/16
Thanks guys this was so helpful! The beeping/chirping was coming from my CO2 monitor as well. I didn't even know I had one until I read these suggestions. Changed the batteries twice from the smoke detectors, removed/unplugged the power of smoke detectors, turned off the circuits and only after all of this I started to think there was something else...gosh such a relief not to hear that sound after two weeks!!!!


08:54PM | 06/14/16
On of our detectors First Alert is chirping every do I get it to stop!!!????


10:06PM | 07/20/16
I have three hardwired smoke detectors in the hallway of the second floor rooms. The chirping started when the coffee maker we brought upstairs is in use. That's fine, we can live with that. One hot day I turned the window A/C on and the chirps came back, with a vengeance. Now it will chirp at random. Time to replace it after all it's over 10 years old.This did not resolve the problem, I search the ceiling for another smoke detector or gadget, nothing in there. I took all three smoke detectors and to my amazement the chirp did not go away at all. There is no way the wiring will make a sound? I put all detectors back and listened. Now there is a continuing chirp at the master's bedroom, bad news, the wife can't sleep with even the slightest distracting sound, but she snores, and I can sleep over it. Then I listened and its not the smoke detector chip, it was from the window alarm lo-batt. Problem 2 solved. Went back to the smoke detector problem and listened very closely, it sounds like it's coming from the ceiling, I listened through the vent, it's not coming from up there 100% sure. It's in this room where the window ac is. Then I remembered plugging in a carbon monoxide detector and it's in the outlet by the wall obscured by the door to the bathroom when open. Sure enough, indeed it is the carbon monoxide detector that was chirping when it senses voltage drop at the circuit where it is tied up to with the A/C and the coffee maker. Problem solved, and it's a blessing I changed my old smoke detectors to new ones.
So I suggest listen very closely, bring another set of eyes and ears. There is no way the wiring will sound by itself, it has to be another gadget, temperature, or electrical noise ie. voltage surges/drops.


10:08PM | 07/20/16
I have three hardwired smoke detectors in the hallway of the second floor rooms. The chirping started when the coffee maker we brought upstairs is in use. That's fine, we can live with that. One hot day I turned the window A/C on and the chirps came back, with a vengeance. Now it will chirp at random. Time to replace it after all it's over 10 years old.This did not resolve the problem, I search the ceiling for another smoke detector or gadget, nothing in there. I took all three smoke detectors and to my amazement the chirp did not go away at all. There is no way the wiring will make a sound? I put all detectors back and listened. Now there is a continuing chirp at the master's bedroom, bad news, the wife can't sleep with even the slightest distracting sound, but she snores, and I can sleep over it. Then I listened and its not the smoke detector chip, it was from the window alarm lo-batt. Problem 2 solved. Went back to the smoke detector problem and listened very closely, it sounds like it's coming from the ceiling, I listened through the vent, it's not coming from up there 100% sure. It's in this room where the window ac is. Then I remembered plugging in a carbon monoxide detector and it's in the outlet by the wall obscured by the door to the bathroom when open. Sure enough, indeed it is the carbon monoxide detector that was chirping when it senses voltage drop at the circuit where it is tied up to with the A/C and the coffee maker. Problem solved, and it's a blessing I changed my old smoke detectors to new ones.
So I suggest listen very closely, bring another set of eyes and ears. There is no way the wiring will sound by itself, it has to be another gadget, temperature, or electrical noise ie. voltage surges/drops.


01:40AM | 08/03/16
Someone commented that a spider was inside their detector and triggering the alarm . Well, just found one in mine too! It fits the issue I was experiencing: three loud chirps as if it was going to set everything off then nothing--kept happening at random times this evening. Finally it decided to hang out on the sensor because all the alarms were triggered.


09:52AM | 08/24/16


06:14PM | 08/28/16
IT WAS OUR CO2 detector chirping also!!!! After hours of replacing batteries and going to the store and buying more batteries for the smoke detector, it wasn't even the smoke detector at all!!!!

THANK YOU SO MUCH my ears are still ringing from the annoying sounds.....


09:05PM | 09/16/16
After replacing the smoke alarm completely several times, much to our surprise we discovered that from the factory the battery was placed in the smoke alarm backwards. There was no connection being made so this thing chirped and chirped and chirped. Reversing the battery so that the connectors actually connected to something fixed the problem instantly. I would love to charge First Alert for all the time that we have spent and all the money we have laid out trying to fix the chirping in our smoke alarm. We bought three new Cfirst Alert smoke alarms and all three had the batteries in backwards. If this is standard procedure, the instructions should tell you to turn the battery so that the connectors work. And by the way, there was no pulltab in any of the three new smoke alarms. The instructions should be updated.


01:46PM | 09/17/16
I have turned the circuit breaker off to try and reset when I hit the test button there's nothing it's hard wired w/ battery back up


09:21PM | 09/24/16
Ahhhh! It was my Co2 detector as well. I bought a new detector, had another replaced under warranty and replaced all wires. I went to the store 3 x. Thank god I found this forum! I was ready to call an electrician. There was a Co2 detector that I had forgotten about. My wife and I both swore the noise was coming from the fire alarm! What a bunch of craziness for nothing!


07:21AM | 09/25/16
BV001656 - Thanks! Tried compressed air and evicted a little spider. No more false alarms!


07:23AM | 09/25/16
Thanks! Tried spraying with compressed air and evicted a little spider. No more false alarms!


11:12AM | 09/25/16
After reading about how hard it is for the human ear to localize where the beep is coming from...and realizing that it is not logical that a beep is coming from behind the wall when all of the power to the house is shut off & batteries removed....."Please please check your CO monitor if you have relentless beeping, even if you swear it couldn't be".....Well, I checked the CO monitor. Yep...listen up....CHECK THE CO MONITOR!


10:13AM | 10/08/16
AH! CO2 Monitor for me as well!


11:11PM | 10/15/16
Been in this place 1 year. Tired of the chipping and talking and lack of sleep.... I just loaded my 357


10:10PM | 04/18/17
My smoke alarm went off three times last night as well. It's done it once before months ago, but not since. It's ALWAYS in the middle of the night...I don't know why that is. I'm thinking it must be a bug (or something) setting it off. It's certainly NOT a nice way to wake up though! When smoke detectors chirp once every 45 +/- seconds it means the battery is low. Mine also do this (in the middle of the night). I have found that I not only have to remove the battery, but also unplug it. Then you can hit the 'test' button to drain the remaining charge. Leave the smoke detector unplugged and without a battery for 2-3 minutes to make sure it doesn't go off anymore. If it doesn't, you're clear to replace the battery and replug in the detector.


07:45PM | 04/30/17
Thanks for all the posts about the issue. Turns out that it was a Carbon Monoxide detector near the smoke detector which was causing the beeping in our house


10:51AM | 05/02/17
The same thing is happening to me! Except it goes off annoying (beep beep beep) for 2-10 minutes, and then stops. Then 8-20 minutes later it starts again. I have a 200 square foot little cabin- only 1 smoke detector in the whole place. I took the smoke alarm down, unhooked it from hard-wires, took the battery out. The sound was coming from the ceiling! Once it stopped, I threw the alarm itself on the front porch and tried to go back to sleep, only for the beeping to start up again coming from the ceiling! I shut all the circuit breakers off and that didn't even work. How is this possible? It has happened 7 times- that is too many to be mistaken about where the sound comes from.


07:28PM | 05/25/17
My smoke detectors have been beeping, 3 beeps, at night when the temp in my bedroom drops. The detector in my room is the trigger. I opened my bedroom door and it stopped when the temp equalized. Going to try with the door open tonight and see what happens.


04:38PM | 07/31/17
We have the same exact issue going on and it is driving me we removed the smoke detector in one bedroom about 2 years ago (there are 3 others in a 10 ft radius so we have lived without the one) we just started to hear a chirping sound and it is definitely coming from the hole in the ceiling where the smoke detector used to be 2 years ago. we replaced the battery and put the old unit up but it continued to chirp..i have the same question...can the wires chirp somehow without a unit? i cant figure out how to make it go away and we are going crazy please help!!!!


07:43AM | 09/18/17
Just had three chirping alarm in the ealry morning was the first alert carbon monoxide detextor next to firex alarm that was the problem? Always in the early morning for some reason


12:42PM | 11/12/17
When the backup battery gets low in about 1.5 years, replaced it. Alarm still goes off even after reset. Throw away bought different brand. It works till the backup battery gets low again. Same thing. Do not know why? I will just put a regular 10 year battery life and no hard wire, which has no problem. Any other solution?


08:25AM | 11/16/17
Had the three chirps every forty five seconds issue this morning at 4am. After checking for a fire, I read lots of internet threads and changed the battery (it's a hardwired unit with backup) to no avail. It's a First Alert combo CO and fire alarm. Finally took it off the wall and read on the back:

Three chirps per minute: Unit is defective. Replace unit.

It was six years old btw. It could also be the clogged sensor, but I didn't want to invoke the vacuum or compressor at 4am with sleeping roommates, so just disconnected it for now and opened my bedroom door for temporary alarm coverage (there's one right by my bedroom door) until I can get to home despot. Since this thread has a high Google index, hopefully I save someone some frustration.


09:58AM | 11/24/17
Is there some other kind of detector nearby that could be chirping and misleading you??....that has happened to me.....check on it.


09:12AM | 12/04/17
So grateful for finding this post after two days of doing all of the recommended resets on my smoke alarm a million times. Googled one last desperate plea and found this. And, yes, I immediately realized the room that I was working on the smoke alarm also had carbon mono detector. I put my ear down to it to wait for the beep - it nearly deafened me. I too would have sworn it was coming from the ceiling. A quick battery replace and the torture has ended. Thank you all for sharing!!


01:11PM | 12/04/17
What happens if I disconnect all four of my hardwired smoke alarms, take out the batteries and press the button to drain the memory? Will they stop chirping and go dead? This is only temporary until I can get them fixed. I will put up battery powered alarms in the meantime. There is a two week wait for an electrician. Everytime, it dropes below 25 degress outside I get the early morning chirp. They all have new batteries, have been cleaned, and have been reset. There is no other alarm in the house and no CO monitor.


10:04AM | 01/09/18
We've had the exit same symptoms over the last several years....cleaned thoroughly replaced batteries etc etc. What now seems to happen is beeping (not chirping) after we come home from a couple of days absence and it gets cold in the house. Temperature seems to be an issue.

I'm not buying six new ones at $50 each until they come out with something better.....Ranch


05:27PM | 02/11/18
I moved into a house with hard wired smoke alarms with back up battery. Now the low batteries are chirping. I was able to replace the battery in the normal 8' ceiling. I am unable to reach the one waaaay up on the vaulted ceiling. So now chirp, chirp, chirp, chirp until someone with a very very tall ladder can get to it.
Question: When someone can reach & remove the back up battery, can the battery NOT be replaced to forever end the obnoxious chirping. Will replace with a better regular battery one to put at the more reasonable 8' height. Very faithfully replaced the batteries on all battery smoke alarms at the old house - so keeping them up to date is not an issue (the reason for inventing the horrible hard wired ones).
-- Bird lover that hates this chirping bird


03:00PM | 02/16/18
One thing that fixed it for me was taking off the cover and bending the metal tabs that touch the battery leads. Apparently they were not making contact with the new battery.If you bend them so they press harder against the battery it could fix the issue. That's what worked for me.


06:41PM | 02/27/18
Same problem as everyone else. I have three floors and the top floor was going off. I waited on hold with Kiddie and after 2 and half hours of their trouble shooting they agreed to send a new one. New one came today and I replaced it then it started the same chirping as the old one???? I ended up using compress air and cleaned it as well as the other two. Still chirping. So I thought maybe one of the hardwires was off or making bad contact. I noticed the one on the third floor (attic above) have puffs of air coming down from the attic. I have blown insulation up there I assumed maybe dust is being blown into it from above and causing it to go off. Its a combo one and only the fire is going off. So I will try and foam seal around it so that its airtight from the attic above and see if that fixes the issue.

Anyone elses that's doing this chirping thing the one on your top floor with the attic above too?


02:47AM | 06/29/18
Just like the others I could have sworn it was the smoke detectors, but after 2 hours of having them all unplugged and batteries taken out... I tried the CO detector, and that was the problem. A battery had exploded inside the CO detector.
I wold have bet money that it was coming from the ceiling of the smoke detector, but it was the CO detector.


01:27PM | 07/06/18
I'm another one who couldn't figure out why my smoke detector wouldn't stop beeping even after changing the battery...until I read this thread and discovered it was the nearby carbon monoxide detector. My dogs and I thank you.


01:28PM | 07/06/18
Member Since: 07/06/18
1 lifetime posts
I'm another one who couldn't figure out why my smoke detector wouldn't stop beeping even after changing the battery...until I read this thread and discovered it was the nearby carbon monoxide detector. My dogs and I thank you.


07:08PM | 10/03/18
Our hard wired smoke detectors kept beeping. We did everything they said to do and they still beeped. We took them off the ceiling and removed the batteries and all 7 holes beeped as if they were still there. We had to sleep in the house with all the beeps, the dog wouldn’t even come in the house. After trying everything again, my husband called the firemen. They came complete with truck and went through the process over and over. Then one of the guys found a c02 detector that was chirping and then two more. We had a new heating system put in last year and they left them on shelves without telling us. They were talking to the smoke detectors and keeping them going. Once we put them out in the garage and reset all the alarms, we have peace. The firemen said that we were hearing the c02 detectors and the beeping wasn’t coming from the empty holes and our house wasn’t haunted. I’m still not convinced


07:54AM | 12/04/18
Had the "phantom beep" problem, hearing beeps even after we uninstalled one hard-wired detector and one battery-only detector. They were on dining room table, batteries out, but beeps still seemed to be coming from ceiling.

Then I took them both into the garage, some distance, and beeps stopped. I'm thinking the beeps were coming from the detectors but audio illusion that noise was in ceiling.


10:05PM | 12/07/18
Tonight I experienced what has been described here. Hard wired detector in guest BR started beeping/chirping - every 30 seconds or so. I changed the battery, took the entire unit from the ceiling and still beeping I swore came from the hole in the ceiling. I called a neighbor and my Son in another state and was prepared to call the fire department tomorrow. Then one of the posts here mentioned a CD detector.

I had removed a CO detector (unintentionally) from the wall and just hadn't gotten it reattached yet. After a few hours of fuming and researching, I started looking for the CD detector and located it on a shelf on the other side of the bedroom in which I just dismantled the smoke detector - I repeat, other side of the bedroom - that was it. The CD detector is now sitting beside me, battery removed, but also no beeping. My Son and I had a good laugh but I will sleep tonight.


06:56PM | 03/10/19
we are having the same problem so where is Bob Vila to help?


12:07AM | 05/07/19
After hours thinking it was in the ceiling. Removing all smoke alarms and still hearing it. Reading this and removing my downstairs CO monitor and still hearing the torture of the chirping. I realized i had a CO monitor upstairs.... No more chirping.. Thank you for suggesting the CO monitor and know it wasn’t in the ceiling and I could have agreed with everyone on this “ Yes its in the ceiling” lol it wasn’t. CO monitor was the solution.. Thank you.


06:22PM | 05/18/19
After six days of beeping, removing all the fire alarms, paying an electrician to come out and check the ceiling wires that seemed to be beeping, we found an ancient CO detector in a basket about three feet away.


08:14AM | 05/26/19
We returned home after a brief 3 day vacation to the chirping noise. I have replaced all 5 hardwire smoke detectors but still same problem - a single chirp about every 25 seconds. Last night I removed all the detectors and put them outside in my truck. Still chirping. A few minutes ago my wife decided to run the dishwasher. BINGO! Before we left we had opened the door to interrupt the dry cycle and forgot to close it back. The dishwasher has a chirping alarm on it.

The point I would make is that the hardwired system cannot chirp if all devices are disconnected and batteries taken out. Look for an unknown device or an appliance.


08:46PM | 06/01/19
Had dame issue and turned out to be a C02 detector with low battery located near smoke detectors....


09:04AM | 06/26/19
Member Since: 06/26/19
1 lifetime posts
I think the problem is with its wiring. Please check if it is installed properly or not.


05:04PM | 07/25/19
Same problem as most on here: Wired Smoke detectors with battery backup. Continued beeping after replacing battery. Turned out my wife had placed (long ago) a battery operated CO detector on top of a cabinet (out of sight), which was on low battery. The sound must have been bouncing off the ceiling making me think that the smoke detector was the culprit. Replaced CO batteries and now blessed silence.


11:04AM | 09/19/19
My BRK smoke alert indicated needing a new battery at 4:30am yesterday. I dutifully changed it with one then another new battery, to no avail. I shook it, swore at it, wriggled it and lo and behold it stopped beeping....until 4:30am this morning. So, I got on my ladder (72 year old spritely woman)and pried the unit from the ceiling, unplugging it as recommended and...beeping continued! I did what was suggested on this thread and took the batteries out of my CO unit, to test and then looked around for another culprit. Yes, my Simplisafe speaker was plugged into a nearby parallel wall (staircase separating them). I unplugged it and NO MORE PHANTOM BEEPING from my ceiling! I will replace my smoke alert as it’s older than14 years and should be updated. With all these wireless goodies in our homes today, the internal wiring systems don’t seem to appreciate how things are changing. Hope this helps others!


07:33AM | 10/05/19


08:36AM | 10/05/19
THANKS SO SO SO SO MUCH to the post from BV001591 on 7/22/13. We were having the same problem and replaced the detector I don't know how many times and it would just keep on beeping.

What do you know...It wasn't the smoke detector at all. It turned out to be the CO2 monitor located near the smoke detector! SO GLAD the chirping has stopped!! Peace...and sanity at last!


08:06AM | 10/28/19
10/28/19 at 4am in the f-ing morning: same situation here....our fire alarm in the master bedroom started chirping and we replaced the battery, disconnected, and the gaping hole was still chirping!!! I knew we had a couple of loose CO2 alarms around the house and remembered there being one in a basket in the master bedroom. Turns out the chirping came from that CO2 alarm in the basket! I pressed the reset button on the CO2 alarm and problem solved! I definitely thought that chirping came from the ceiling!


08:33PM | 11/17/19
So I have a kiddie smoke alarm. It is downstairs by the door from the garage inside the house. It has a vent with filter beside it. My problem is that when my front loading washing machine spins on high, the smoke alarm starts to chirp. Don't get me started on the shitty placement of stuff to save a buck from the damn builder. It doens't happen all the time just on high speed for washer which is located upstairs right over the area. The intake vent is about a foot from the smoke alarm and is not sucking in air (AC and heat not running) when this occurs.



06:29AM | 12/11/19
This old post saved my sanity lol.

I took off the dumb smoke detectors, put them in the garage and STILL heard chirping. Wouldn’t have thought about CO2 detector if I hadn’t read this post because I didn’t think we even had one in the bedroom, just thought there was one outside the room. Turns out there was one in a drawer we had removed a couple of years back and never took the battery out!


12:37PM | 12/23/19
I am
having the same problem in my house, chirping noise after batteries replaced with new in the smoke detectors, Removed them, put them in exterior trash can, and still chirping noise, but it sounds like it is coming from the ceiling fan, not sure. It Just started. I replaced battery in detectors.. Mine are not hard wired. Still chirping noise. So I put another new battery in the unit. Still chirping previous person described problem.Why at 3:00 am??? My dog goes psycho when it chirps working herself into a hot sweating tizzy barking loud enough the neighbors can hear, I am sure. No sleep here and scared my dog will stroke out or have heart attack it bothers her so much. Someone please reply. Thank you! Do ceiling fans chirp the same? Sounds like it here. Took ceiling fan apart and cannot see it has battery anywhere. It is Used fan, so no remote here. I am going to turn psycho soon, same as my dog with this noise. Where could chirping be coming from????????


08:26PM | 01/12/20
I had same noise in bathroom coming from ceiling, went to attic above bathroom no noise, searched everywhere, shutting main circuit breakers off, which was still chirping. I noticed sink hot water faucet dripping, took apart, tightened, it stopped dripping and that crazy chirping, exactly like smoke detectors with low batteries. Strange though, noise was not coming out of faucet, traveled high into ceiling. Thank God was figured out, drove all like house was spooked!!!


02:19PM | 01/17/20
Thanks for the posts pointing out possible OTHER plugged in CO2 alarm.

Had similar problem, thought it was the hard-wired ceiling alarm, but continued to hear chirping every 40 seconds even after I disconnected the unit. I was still standing up on the stairs, about to plug the unit back in when I thought I heard chirping sounds from the hole.

Luckily I read the postings about CO2 alarm, finally found a plugged in less than 10 feet away near the floor that's low in battery. Check surrounding area for other possible plugged in alarms with backup battery.


12:48PM | 01/21/20
I have hearing impaired smoke detectors but they randomly sound off like chirping and the lights are still green so it doesn't look like the batteries need to be changed however there over 10 years old what's wrong


12:46PM | 02/19/20
Same exact issue as initial post: it was the CO detector! Has the same sound as the smoke alarms (WHY??).
Thanks so much, everyone!!


11:26PM | 02/25/20
This is the best thread I have read in a long time! After a week straight of ear plugs and anger, taking a vacation day to troubleshoot and replace all the hard wired smoke alarms, and countless hours googling for answers, we found the exact issue in this thread... had to be the poltergeist in the wires in the ceiling. And yes, we, too found it to be the CO2 detector! Best comment above... after all these years “ why hasn’t Bob Vila answered us yet?”


07:47AM | 02/26/20
Member Since: 02/19/20
5 lifetime posts
There was a similar problem. Need to clean, it's because of the dust.

Sometimes dust finds its way into your smoke detector and gathers in the sensing chamber, which can cause your detector to chirp.

Dust can also cause false alarms, so if you’ve heard your alarm go off at random times, that could also indicate you have dust built up in your detector.


01:15PM | 03/27/20
Loved reading this thread... Experienced the same thing everyone else did.

Chirping smoke... Replaced battery and it still chirped ever 60 seconds. Removed the unit tripped the breaker to the room and held reset on device for 30 seconds. Still chirped. Replaced unit... And while I was holding it in my hand it chirped from the ceiling.

Finally after about a week I sprayed compressed air into the base of the unit in the ceiling. That did it... No more chirping!


10:48AM | 04/05/20
For us, IT WAS THE CARBON MONOXIDE ALARM!!! We REMOVED the hard wired smoke alarm and the chirping didnt stop. I followed the thread about the CO alarm and solved our issue!
Why do these things always seem to happen at
2:30 a.m. ????????


03:48PM | 04/11/20
Just had same issue until I realized the chirping that seemed to be coming from the ceiling was coming from behind a chair where there was a kiddie carbon monoxide plug in detector chirping..I took the batteries out and thank goodness it stopped!


10:02PM | 04/14/20
Mine was the same solution as some of the latest posts. It was the carbon monoxide detector with a dead battery. The chirp was identical to the smoke detectors. We had tried every other solution, so when someone mentioned a carbon monoxide detector, the light bulb went off, so to speak.


12:18PM | 04/20/20
Check CO2 detectors! I had same problem, eneded up being a sneaking little CO2 detector failing.


08:01PM | 04/27/20
I have hard wired smoke alarms with battery backups. One of them has gone off a couple of times (5:30a.m.), both times. Battery is new. What could be the reason?


11:22AM | 04/30/20
All of our detectors have been removed (after replacing the batteries and resetting didn’t help) we turned the power off to the whole house and the chirping from the hole in the ceiling continues. We do not have a CO monitor at all in the house and never have. The house is about 20 years old. Yes, the detectors are old and need replacing, but the sound isn’t coming from them, it’s coming from the wiring in the ceiling. How can it chirp with no power?
Super frustrated.


09:35PM | 05/17/20
We are having the very same issue. It’s driving us crazy. If there is a CO2 detector in this house, we have never seen it and we’ve lived here several years. It’s an all ele. house, no gas lines in it at all. (that we know of). As a last resort my husband is going to the attic tomorrow to check for one there. If not, I we have no idea what to do!!! IF ANYONE HAS INFORMATION- PLEASE HELP! We also have bought a Kiddie and tried to replace it.


10:20PM | 05/19/20
I had the same type of issue with a old detector going off at night, replace with new, next one does it, replace with new, NEW one does it . . ??? Mine don't chirp, it's a full single blast. You know that blast, the one that bolts you out of a deep sleep. But unlike the previous posts I look at the detectors and the ones that have gone off have a BIG RED solid light. They are Kidde brand and new. So the quest for a answer marches on.


11:10PM | 05/27/20
Based on many years troubleshooting these type of issues:
1) Make sure the beeping is actually coming from a your smoke detector, not a carbon monoxide alarm. If the beeping is coming from a CO alarm, look at the manual or back of the device to decode what the beeping is trying to tell you. Different beeps mean different things (Low battery, detector end of life, etc.)

2) Systematically troubleshooting malfunctioning detectors can be simplified to main problems.
a) Power
i) Hardwired - 120 v. (No power, miswire, proper grounding and neutral/ground bond at panel only)
ii) Battery - Missing or low / weak
(If you get the single beep only at night, this can happen when your house gets cold. As a weak battery gets cold, voltage decreases slightly causing the low battery chirp during cooler temperatures)

b) Sensor issue
i) Dirt, debris, spiders, etc. (Vacuum)
ii) Environmental - Showers / cooking vapors / HVAC vents blowing dirt.

c) Malfunction / circuit problem
i) Detectors should be replaced after 10+ years. If you have a single detector malfunction, it can cause all interconnected alarms to sound. Identify the problem detector and replace. (Usually the activated detector will have a different LED color compared to the others that are sounding). If you have different detectors that are randomly sounding, it less likely to be this issue. Could be power problem or RF interference.

d) RF interference
i) An unusual situation, but there was one person who had multiple hardwired detectors activating at random times during the night (different times). After he replaced all the detectors the problem continued. He again replaced all the detectors with a battery only type, but still had the problem. We isolated the issued to a neutral / ground bonding at the dryer caused by an improper dryer cord connection. Simple fix that solved the issue. If you want to check yourself, just pull up the installation manual for your dryer and read up on 3 vs 4 wire connections. This issue can also occur with improperly installed sub-panels as well.

Some questions to help you (or electrician) troubleshoot the issues:
1) Are the detectors wired or battery or both?
2) Are they interconnected or stand alone?
3) Is the problem with a single detector or multiple detectors?
4) What time of the day does the problem occur / re-occur?
5) Is there a common temperature / time relationship?
6) What appliances start up or shut down during those time frames?
7) Have there been any other electrical issues in the house? (Power problem or RF interference)
8) When were the detectors last replaced? (Date code should be on back of the detector)
9) Have any of the detectors been recalled? Check consumer product safety commission?
10) Was there lightning in the area at the time of activation?
11) What were people doing and/or electrical items running when the activation occurred?

Hope these suggestions help. Nothing worse than detectors malfunctioning and ruining sleep.

Good luck!


11:35PM | 05/31/20
It was CO2 alarm that caused it that was close to the Fire Alarm.


10:50AM | 06/03/20
Thank God I found your post. We had the same thing at our house.






02:46AM | 06/08/20
Beeping in the celing..f
Removed all 6 smoke alarms, drained them all turned off electric put alarms outside...ceiling still chirps, went up to attic, nothing electricity to the hard wire alarms and no alarms
Still churps... any ideas
Should Icall an electrican


03:36AM | 06/27/20
Mine ended up being a CO2 detector also that was in the hallway. Thanks goodness for these postings. Good night. Sleeping is wonderful.


08:58PM | 06/30/20
It's CO carbon monoxide not CO2 carbon dioxide...


04:55PM | 07/10/20
This post saved us!!!! Like many others, we were going crazy with the chirping sound, which continued even when the smoke alarm was completely unplugged

It was the carbon monoxide detector! We couldn't believe it.


01:55PM | 07/21/20
Member Since: 07/21/20
1 lifetime posts
It's the CO2 detector. I could friggin' HEAR the beep coming from the wires in the ceiling, I SWEAR I could. There was a CO2 detector at floor level (where they're supposed to be), hidden by some shoes and a broom. I spent two friggin' DAYS figuring this out, bought two different smoke detectors. The clue is this: if the green light is lit and not flashing, not red, then the smoke detector ain't it. And if you take the detector off and drive it to the next county, and when you go back home the ceiling is still beeping at you, then you know it ain't the wires, ain't the smoke detector, it's almost certainly a CO2 detector somewhere. Just remember to look at baseboard level for the little dickens.


11:32PM | 07/21/20
Had the same problem. Chirps from the walls and detector disconnected. After reading this site, went down 5 minutes ago to the Den and looked for the dang CO2 detector. Sure enough. Replaced the batteries in it and silence is golden. Thank god.


08:55PM | 07/26/20
How and what do I clean the inside housing where the smoke detector is connected in the ceiling? There is s lot of dirt which may be causing my detectors to go off at the samr tome even though there is no smoke in the house.


08:58PM | 07/26/20
Can I use compressed air to clean the inside of the ceiling where the smoke detector is connected because of the dirt inside.


05:09PM | 08/04/20
We had the exact same issue, did all the above, removed all batteries and detectors, etc, etc, still sounded like it was coming from the ceiling, which made no sense, but sure sounded that way
Finally checked the nearby CO2 detector, and that was it!
Changed the batts in that, chirping went away!


10:18AM | 09/29/20
It is now 2020, but I still felt obligated to provide a response as I was having the same issue. I had removed the smoke detector and the beeping still continued (from what I thought was the wires/ceiling. I wventually realized it was our Corbin monoxide alarm that was plugged into a wall in the same area of the house. Hope this helps


08:03AM | 10/02/20
I had the same issue - mysterious beeping from a smoke detector wiring only (no installed unit). Stood directly beneath the opening and was convinced this was the source. Then read the posts about the possibility of a different device emitting the sound instead. Of course! I remembered my Verizon battery-backup unit installed in the same room and sure enough the “replace battery” light was on. Disconnected the dead battery and voila - no more beeping Thank you for the tip!!


05:00AM | 10/10/20
This just happened AGAIN to me @ 1:30?am.
This is very unsettling. The alarm went off, then stopped on it’s own, but continues with red ring then amber ring lighting up. I unplugged it, and still it continues. Can’t sleep now. No smoke. No fire noted. I replaced these 13 months ago. Supposed to last for 10 yrs. sealed battery, so can’t change a battery. I recently had canned lights installed. Any chance the dust from the install made them alert?
This is an awful feeling in the middle of the night!!
Smoke detectors should sense smoke, not dust.


04:21PM | 10/10/20
My goodness, We had the same problem as a number of you — intermittent "chirping" every 45 seconds from a mysterious location. I removed every possible smoke detector (unplugged from ceiling) as well as removed all the batteries — still chirping!!

We were 100% sure we didn't have any additional smoke/CO detectors lying around anywhere. The chirping sounded like it was coming from the ceiling, localized in one of our bedrooms. I spent three hours crawling around in the attic, digging through "cotton candy" insulation, trying to find a dying smoke detector that may have been left up there somewhere. What a nightmare!

Turns out, my wife had left a spare CO detector sitting in a basket atop our bookshelf. She had sworn we didn't have any of the damn things anywhere.

The way I finally found the thing was by using a free decibel detector app on my smartphone. Every time it beeps you read the meter and then move closer to the sound (getting warmer!) -- finally after 4 days of chirping I figured it out.

Not a great experience.


07:29PM | 11/08/20
OMG thank you!! It was the CO2 monitor... I was having the same mystery issue of "impossibly beeping wires" haha!!


09:26AM | 11/26/20
We had the same issue. Changed the battery and it was still beeping. Thought it was insane to be coming from a hole in the ceiling with nothing but wires hanging out. Turned out that it was a CO2 alarm on the floor in the same room.


12:34PM | 12/05/20
My smoke detectors were chirping, but the batteries were not due to be changed. I took all of the detectors down, removed the batteries, cleaned all the contacts and still chirping was coming from the hard wire area in the ceiling. I turned off the electricity for the house, waited a few seconds and turned back on. Still chirping. Discovered that the disconnection of the electricity meant that I needed to reset my internet modem. After I did that, the chirping stopped. There is some kind of connection between the smoke alarm hardwiring and the internet apparently.


07:51PM | 12/06/20
Same problem, removed all the smoke detectors and the CO detector checked in the attic and still sounds like the chirping is coming from the wiring that was left behind that plugs into the smoke detectors. Kidde models. Both about 2 years old, the third one is older. But this is nuts. It's been chirping for about a month now, every minute or so. Cannot find where the chirping is coming from other than the wires! This is nuts!


03:58AM | 12/11/20
I'm so happy I found this thread. On Monday morning, at 6:00 a.m., the smoke detector in my bedroom began to chirp (or so I thought). It's hard-wired in, and I live in an apartment complex. Reported it to building admin. Tuesday it started at 5:30 a.m. Wednesday it started at 3:00 a.m. Thursday it started at 1:30 a.m. And the chirping would go on for 5 to 6 hours! The technicians came, they checked the system, could find no problem. Thursday afternoon, they took the detector out, said they'd replace it. I was awakened at 3:00 a.m. by chirping, again, seemingly coming from the ceiling. ARGH! So, I got online and started searching, and I found the post that said to check the CO2 monitor, even if you're convinced the sound is coming from the ceiling. I had a monitor sitting on my desk in the bedroom, carried it into the living room, and yep, the sound was coming from it. Now I feel really stupid, but at least I know I'm going to be able to sleep. So, thank you so much for saving me from going insane.


11:58AM | 12/15/20

OMG, I am also so happy to have found this thread. Exact same thing happened to me, and I thought my ceiling was possessed! I saw the comments about the CO2 monitor, and I even have one right in that same hallway, but because it plugs directly into the wall, I didn't even give it a second thought. And then it hit me—DUH, I bet they have backup batteries, too, and it's telling me that those are dead!

And, VOILA. That's what it was. I hope this helps!


10:02PM | 12/22/20
Our mystery lasted almost 24 hours, and just now got it solved after 2 hours in the middle of the night last night and about another 2 hours tonight after work. We went as far as killing the power, and the wires were still chirping (somehow?) with the smoke detector in the garage with the battery out and juice drained. After reading through some of these posts, knowing that we have CO2 detectors, I looked to see if one was close to the smoke detector we thought was causing our problem. Just as I spotted it plugged into the wall not far from the smoke detector, it chirped and flashed. That was our problem....not the smoke detector!!! UGH!!!! Chirps can be VERY deceiving.


10:16PM | 12/25/20
I had same issue. After reading these logs I went and checked for any carbon monoxide unit near my smoke alarm. Yep! I replaced the 9 volt battery in that carbon monoxide unit and the chirp stopped. So reckon that chirp was bouncing off the walls and making me believe the chirp was coming from wires in the ceiling where I had disconnected my smoke alarm unit. WOW, so thanks for everyone’s info and solutions.


02:22PM | 01/10/21
I finally disconnected all fire alarms, put them in a pile to verify the sound was not coming from them. I then looked and listened for any other sensors, as sound travels in strange ways. it was in fact, a plug-in CO2 sensor. I pulled out the batteries and the problem was SOLVED.


11:43AM | 01/22/21
Thanks everyone. Same problem. CO was the case here too.


06:49AM | 02/05/21
I’ve been up for two hours this morning, since 4 AM trying to stop my chirping wires after removing my smoke alarm. I tried everything, including the breaker switch. Then I read on this site that a nearby carbon monoxide detector might be the culprit. I swear the sound came from the smoke alarm, but it was coming from the carbon monoxide detector. I never would have figured this out without reading this here on the site. I was ready to go without power or move or something. I’m going back to bed.


02:13PM | 02/08/21
Ours beeps every few minutes for a day . We think we reset it have changed all the batteries. Have taken them done and even turned off circuit breaker and can not stop it HELP


04:46AM | 02/12/21
My hard wired/ battery units did the same thing.
Call your local fire department and they should come out ( gladly) and try to help you out.
I was told one was bad and setting off the others. Went back to replace at the local Lowe’s and they would not replace it but call the number on detector and they should send you another one if it is <10 yrs old.
Hope this helps... I really dislike these hard wired detectors but they were here before we were!


08:04PM | 02/15/21
I have the same problem and have done everything that has been suggested. I do not have a CO2 detector and the chirping is DEFINITELY coming from the ceiling. This has been going on for over a month with intermittent chirping from the wiring in the bedroom ceiling. My dog is also going nuts. :) I am going to call an electrician (2nd time) and see if they can unhook the wiring and I'll buy new battery smoke detectors (after spending over $100 to replace the hardwired ones already). I'll let you know what he says.


10:26PM | 02/16/21
I’m comforted in some measure that I’m not alone in my torment! I don't have any solution to offer, rather, I want to share what has saved me from insanity. My apartment building has hard wired smoke alarms, no chirping since I moved in over a year ago. This past December, a week after they went through the whole building checking all alarms, replacing old ones, batteries etc., the chirping started coming from a weird ceiling/wall spot in the outer hallway between my apartment and my neighbors. I suspect a faulty battery or connection and they need to trace which alarm isn’t working properly. The maintenance guy refuses to even try to figure it out, it’s gone off every 28 seconds (I’ve timed it) for almost 3 months, it NEVER stops! I can hear it even in my bedroom with the door closed, there’s no escape. I found a personal way to cope that may help someone else. I’m not affiliated in any way, just saying that first, but I have the app “Naturespace” and have downloaded several of their recordings that have a lot of bird song. I know what you’re thinking, but it’s amazingly effective! I don’t even hear the smoke alarm chirping unless I have the sound too low. The recording I use the most is “First Light”, which I play over my bluetooth all day and at night I play an Icelandic waterfall called “Dettifoss” which masks really well. I’d rather have the option to have a quiet apartment, but since that option has eluded me, I have to live in a what sounds like a bird sanctuary. It was hard to adjust to at first, but now it has saved my sanity.


01:05PM | 03/13/21
Smoke detectors chirp when they have any error condition, not just a weak battery. This includes a broken sensor. Follow the manual to reset the detector, but if it persists, replacement is the only option.

Smoke detectors going off, with a false positive (obviously make darn sure it is a FALSE positive - CO in particular) is a different problem.

There are rarish conditions that will trigger false positives. In this case re-siting the smoke detector, trying a different type or brand of smoke detector, or one that is better made, is the solution.


10:18AM | 03/17/21


01:00PM | 03/24/21
We suspected that our hard wired smoke detectors were the cause of the beeeping. After an exhaustive course of trial and (much) error we honed in on various electronic devices. The culprit was a battery operated water leak detector alarm with a battery that probably needed to be replaced. Check for rogue electronic devices including old cell phones.


07:01PM | 03/25/21
Exact same issue turned out to be a co2 detector in a closet beeping every 45 seconds drove me nuts for days.


09:47AM | 04/15/21
Thanks to all! It was the CO2 detector all along. It drove me crazy


05:30AM | 05/16/21
Turn off the circuit breaker to the alarms.


12:11PM | 05/23/21
I KNEW that I wasn't crazy! I even had my wife listen to the blank receptacle and confirmed that is where the chirping is coming from. I have switched the Kidde smoke alarm body with one other of the 5 in my home and the chirping continues - even with the smoke alarm removed.

I'm going to try the cleaning and circuit breaker suggestions and will post back.


09:40PM | 05/23/21
Someone needs to bump the above post about the CO alarm to the beginning of this thread. The one in all caps....

The CO alarm is like a ventriloquist. The chirp appeared to come from the receptacle.

Thanks BV024705


02:25PM | 06/06/21
We removed every detector in the house and there was still beeping. After reading this, I remembered I bought a stand alone CO2 detector. THAT was the culprit! Changed the batteries and problem solved.


10:29AM | 06/28/21
I am in West Australia. Have 2 hard wired Clipsal ionisation smoke/fire alarms. Started beeping (expiry 2021). Replaced batteries with brand new 9V batteries. Kept chirping. (I Had released any pent up charge). Long story short. Turned off power, disconnected completely from wiring (wires taped and hanging from ceiling). Still chirping from wiring even with power off. If I'm close to one the other "wiring" chirps and vice versa. I went up into ceiling space, no additional sensor or capacitor etc. Nothing. I'm stumped. New photovoltaic alarms going in Wednesday. If they still chirp I'll call in security alarm people... maybe it's that somehow? Fortunately with bedroom door closed I can't hear it.


12:05AM | 07/06/21
It was the CO2 detector, thank goodness.


11:18PM | 07/16/21
It’s a good thing I read the whole story and I listened to the Carbon monoxide detector and it was chirping and it is next to our bedroom door and my wife looked at me and said I don’t believe it so I changed the battery’s and put it back on the wall and put the smoke Detector back on the ceiling and put the ladder away and it’s time for a crown and seven


10:59AM | 07/19/21
My quick hardwired alarms isssues:
1. two years ago I had the chirp issue. After replacing all alarms we learned it was the CO2 sensor, not the smoke alarms.
2. Just had a redo of the 30-second chirp, luckily mid-afternoon on Sat. all batteries were 3 mos old. After searching everywhere, sounded like it was in the walls...Learned that the builder put one in the crawl space under house! Used my mechanics creeper to get in there and pulled it. need to decide if I should replace or just tape over the wires and cover. At 68 yrs old my future visits to the crawl space are not welcome!


10:24PM | 07/28/21
And another identical issue - after 3 insane nights of 4:30 am beeping a hole in the serving floor ceiling with dangling wires, it was a CO detector we forgot we had. Thanks to this site, saved our sanity!


01:10AM | 08/16/21
So grateful I found this thread! Had a continuous beep in what seemed like our smoke detectors for a week. We changed the batteries and were looking to purchase new SD in the morning. Found this thread and read about the CO monitors and the possibility of the battery being low …We changed out the CO battery and the chirping stopped!!


09:08PM | 08/18/21
I am having the chirping sound but I cannot find where it is coming from. It is clearly in our laundry room, but there are no smoke detectors, CO detectors, or any other kind of alarm in the space. I have looked through every inch of it. It sound like it is coming from within the ceiling, but the ceiling is under my son's room, and I definitely don't hear the beeping there. I am at a complete loss as to what this is and what is causing the chirping. It also only occurs at particular times of the day - usually afternoon and/or evening.


05:23PM | 08/21/21
Same issue here. Chirping every 45 seconds - would stop for a while, then start up again hours later. Tried replacing batteries with multiple new ones, nothing. Tried a whole new detector, nothing. Tried turning off the breaker, disconnecting, rewiring, blowing air, vacuuming, draining the battery, nothing. Seemed like even with it disconnected and without a battery, the chirp was still going and seemed like it was coming from the hole or the wires or something! Called an electrician to book an appointment because we were going crazy (it was in our baby's bedroom and no one was getting sleep!) but was so fed up I searched forums and found this one. Everyone was saying it was the CO2 monitor - we have a separate, battery powered one that sits in the room but we only got it 2 years ago brand new and I was certain the sound was coming from the hole in the ceiling. Skeptical, I went into the room immediately after reading this forum, grabbed the C02 monitor and brought it to another room and YES - it was the CO2 monitor! I replaced its battery and now there is no more chirping and no more torture!


03:22AM | 09/03/21
My power went for 1 1/2 hour power came back on and everything ok. That night at midnight smoke alarm chirped for about 10 seconds. Second night at midnight same thing happened I changed battery. That night at midnight it chirped again. Next day i took smoke alarm down and midnight that night another smoke alarm chirped. Next day I turned circuit breaker off took down all 3 alarms changed battery's and put back up and turned circuit breaker back on. Midnight that night alarm went off again. The alarms are only 7 months old and are kiddie


11:34AM | 09/18/21
It was our carbon monoxide detector too! I sure wish I had spotted that possibility sooner!


08:59AM | 09/29/21
Weirdest damn thing. I was awoken at 4:00 by that infernal chirping. Assumed it was my hard-wired smoke detector in the dining room. Took it down replaced the battery with a brand new one, fresh from package -- still chirping. Did all the "clearing out", holding down the test buttons, turned off the breakers...STILL the damn chirping. Tried to ignore and go back to sleep. Today I've been searching the webs trying to figure out WHAT is enabling the unhooked, unpowered damn thing to keep chirping. READ so many of the above entries ^^^...there is a small CO battery powered detector in the same room sitting on a shelf and it was THAT detector all along. Could have saved me a couple hours lost sleep if I'd figured that out sooner!!

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