On the bottom of the smoke alarm is a reset button, press it!
Most hard-wired smoke detectors include a 9-volt backup battery that's supposed to kick in if your home loses electricity. If that battery is running low, your detector alerts you with a high-pitched beep.
Press and Hold the Test Button
If it's a hardwired smoke detector beeping, reset the alarm the same way, by holding in the test button.
The most likely reason smoke detectors go off unexpectedly is that people aren't changing the batteries in them often enough. In most sensors you might think of, the strength of the signal goes up when they detect what they're supposed to. Common causes of smoke detector false positives around the house.
If your hardwired machines continue to beep in the absence of a battery, it's most likely because the backup battery has become active. Keep in mind that a backup battery unit is only available with a hardwired device, so if your smoke alarm is battery-only, the chirping is coming from somewhere else.
The Batteries are Low: Usually accompanied by a loud beep, a blinking red light could mean the batteries in the unit are low. Consider adding fresh batteries and running a test to make sure it's working. It Needs to Be Replaced: Smoke detectors don't last forever.
Hardwired smoke detectors (which typically include a backup battery) are subject to similar issues as those that operate on a battery only. However, hardwired units often require resetting after problems are addressed. On most, simply hold the reset button for 15 to 20 seconds to silence the noise.
If you have changed the batteries and tried the circuit breaker, but the beeping persists, you may need to try resetting the detector(s): Use the reset button: most smoke detectors have a red reset button. Hold the reset button down for approximately 15-20 seconds.
If your smoke alarm is emitting a single high-pitched chirp every 30 seconds or so, it's most likely a sign that the battery is running low and needs to be replaced.
Try a manual reset.
Remove the batteries and hold down the reset button for 15 to 20 seconds. Reconnect the batteries and alarm. It will most likely beep once as evidence it is working, then it should stop.
If you want to manually reset the smoke detector so that the red blinking light will stop, you can press the test/silence button for a few seconds. If your device includes a keypad press “*72” or if your smoke detector is hardwired, look for a reset button to push and hold for 20 seconds.
For most residential smoke detectors, blinks are common; you need to be conversant with the colors showing. Different smoke alarms use the green and red LED to indicate the device's power status such that a flashing green means low battery while a constant blink means AC power is connected.
A blinking red light on a smoke detector is rarely cause for alarm. Instead, it usually means that the battery is low, or the detector is in need of a minor repair. If you notice a blinking red light, replace the battery first – but only if you're sure that it's still good.
Battery smoke detectors run solely on batteries. Hardwired smoke detectors run on electricity, but they also have a backup battery for power outages. When you hear a hard-wired smoke detector beeping, it means you need to replace its battery.
Many people consider it a difficult job to do. Most people ask themselves, “can I remove a hardwired smoke detector?” The answer is you can！ If you have to stop the hard-wired smoke detectors from beeping, you must unplug them from the clip and remove the battery.
Smoke Alarm Power Sources
Without the battery, neither of these units has the power to go off. Other smoke detectors get hardwired, meaning they tap into and draw their power from the home or building's electricity. Hardwired alarms often have a battery backup just in case the electrical power goes out.
Remove the smoke alarm from the mounting bracket and disconnect the power. Remove the battery (for a sealed-battery model, see Battery Settings for a 10-Year Alarm to learn more). Press and hold the test button for five seconds. Reconnect the power and reinstall the battery.
How long do hardwired smoke alarms last? If you're aiming for the longest dependable smoke alarm coverage, hardwired alarms can easily offer 10 years of protection, in fact every alarm must be replaced every 10 years.
If a smoke alarm is chirping consistently, one of the following may be the reason: The battery may need to be replaced. An alarm will chirp every 30 to 60 seconds for a minimum of seven days. With a "low battery" announcement, disconnect the unit and replace the batteries.
In most cases, you can find the 'hush' button on the smoke detector's cover. However, if you have trouble finding the button or are not sure if your detector has the feature, check out your user manual.