If you find after a few years that your smoke detector has a nuisance beep, even after you have changed your back-up battery, carefully run the soft brush or narrow tool on the vacuum cleaner around the grilles on the side and front of the detector and you will find the beeping stops. The reason is that the build of dust and cobwebs inside the body seems to irritate the sensor.
Most smoke detectors are supplied with a dust cover which is to protect the unit during construction, so make sure its left on until the room is ready for use.
Other possible reasons for nuisance beeping on smoke detectors:
- Weak Battery
- Battery pull tab not removed
- Battery drawer not closed properly
- Battery not making full connection with terminals
If you’ve removed the power and taken the battery out and the detector is still beeping, then the capacitors still have charge stored in them. They can usually be drained by pressing and holding the testing button until the noise stops.