What should you do if a smoke detector makes false alarms?

When a residential smoke detector repeatedly triggers unprompted false alarms while the indoor air is completely clean, you should follow a systematic troubleshooting process to resolve the issue. First, press the central silence button to quiet the siren temporarily. Second, remove the smoke detector from its ceiling mounting bracket and use a can of compressed air or a soft brush to clean out accumulated dust, cobwebs, or tiny insects from the optical sensor chamber. Third, replace the backup battery with a fresh cell. If false alarms persist, the unit's internal sensor has degraded. You can troubleshoot alarm hardware safely by turning off power if hardwired. You can verify that your corrective action is successful when cleaning the sensor or installing a brand-new unexpired replacement smoke alarm eliminates recurrent false alarms permanently.