Why does my smoke alarm keep going off?

Most smoke alarm sounds fall into two categories: either your alarm beeps at regular intervals (chirping), or beeps consistently without stopping (sirening).


Chirping is when the alarm beeps roughly once every 45-60 seconds. This is usually to indicate low battery power. Most of the time, the battery just needs to be replaced. If the alarm is a mains alarm, you might need to disconnect the alarm from its base or plug and remove the battery. Then hold the test button for 10 seconds to drain the alarm of residual power before putting a new battery in.


Sirening is when the alarm beeps consistently without stopping. This usually indicates smoke has triggered the sensor in the smoke alarm. If an alarm is sirening for no reason it will most likely need replacing. Try our troubleshooting tips to try and stop your sirening alarm.

Got a beeping smoke alarm? Try our troubleshooting tips. Alternatively, watch as Detector Inspector Smoke Alarm Technician demonstrates four troubleshooting tips to try if you have beeping smoke alarms.

If you're still having issues and the property you're residing in is enrolled in our smoke alarm safety service, please click here to request an urgent service. Alternatively, call 1300 134 563 to book an urgent appointment.

Other commonly found issues with smoke alarms

Flashing Red

This is completely normal across all alarms as long as there is no sound. If this is accompanied by a chirp every 45-60 seconds then the battery may need replacing.

Flashing Green

On a mains-powered alarm, this is normal and simply means that it is connected to the mains power.


On a mains-powered alarm, this likely means that the LED light has simply stopped working. It may also mean the alarm is not connected properly to the mains, in which case, it will use the battery until it goes flat. The smoke alarm will need to be replaced or the wiring will need to be checked to ensure power is connected to the smoke alarm.

Alarm Chirping & Flashing Red LED

Alarm requires new batteries.

Alarm flashing red LED intermittently

Alarm requires servicing.



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