Hardwired units will have a steady green LED light to show that it's receiving AC power. Battery-operated units will have a quick flash every 30-45 seconds. This does not necessarily mean the alarm is working. Pressing the Test button is the only recommended method.
You can test your smoke alarm by pushing the Test/Hush button on the cover and holding it down for a minimum of 5 seconds. This will sound the alarm if the electronic circuitry, horn and battery are working. In an interconnected installation, all interconnected alarms should sound when the test feature on any one of the interconnected alarms is activated. On smoke only models, the sound will stop immediately once your finger is removed from the test button. On combination smoke and carbon monoxide detectors, press and release the test button, and the signal will go from unit to unit testing the interconnect circuitry as well as the alarm.
If only the unit you push the test button on signals, there's something wrong with the interconnect circuitry either in the wires or in the alarm.
DO NOT use an open flame to test your smoke alarm! You could damage your alarm or ignite combustible materials and start a structure fire. Test your smoke alarms weekly to ensure proper operation. Erratic or low sounds coming from your smoke alarm may indicate a fault in the alarm. Check your warranty and if within the warranty period, contact product support for warranty replacement.
Product Support can be reached at 1-800-880-6788 Monday through Friday 8:00am - 8:00pm EST and Saturday 9:00am - 3:00pm EST.