To test a smoke detector, locate the test button on the cover and press and hold it down for about 5 to 10 seconds. A loud, piercing siren should sound, confirming the battery, electronics, and horn are working properly. Test your alarms at least once a monthSouthernFried » 10 Aug 2026, 6:31 pm » wrote: ↑ Be sure to kiss the wife bye-bye before you leave the house.