10 Best Interconnected Smoke Detectors 2025 in the United States

The First Alert SMICO100-AC is a 6-pack of interconnected smoke and carbon monoxide alarms designed to offer reliable home safety. These alarms use hardwired power with battery backup, ensuring they work even during power outages. The ionization sensor type is effective at detecting fast-flaming fires, making it suitable for general household use. When one alarm goes off, all compatible alarms sound, giving early warning throughout the home — a key feature for interconnected detectors.

Installation is made easier by the secure mounting bracket and included adapter plug, which helps position the alarms correctly. Maintenance is straightforward with a latching alarm indicator that shows which unit triggered the alert or needs attention, simplifying testing and battery checks. While these alarms do not include advanced smart features like smartphone connectivity or voice alerts offered by some newer models, the Precision Detection technology aims to reduce false alarms associated with ionization sensors, which can be prone to nuisance alarms from cooking smoke.

This set provides a dependable option for families seeking interconnected smoke and CO detection without the complexity of smart home integrations.

The FIRST ALERT BRK SC9120B-3 is a reliable choice for anyone wanting a dependable combination of smoke and carbon monoxide detection, especially for homes that prefer hardwired systems with battery backup. It uses two sensor types: ionization for fast-burning fires and electrochemical for carbon monoxide, covering key safety threats effectively. The units interconnect with other First Alert or BRK alarms, which means if one detects danger, all alarms in the network will sound — a great safety feature for larger homes. Powered primarily by your home's wiring but with battery backup, these alarms keep working even during power outages. Installation is simplified by universal mounting brackets and tamper-resistant locking, plus the side-load battery compartment makes battery replacement straightforward. Testing and silencing alarms can be done easily with a single button, reducing hassle during regular maintenance.

These detectors do not have advanced smart features like app connectivity or remote alerts, which some newer models offer for added convenience. Also, while the installation is easier than many other hardwired units, it still requires access to wiring and might be best handled by someone comfortable with home electrical work. This pack is well suited for those who want strong, no-nonsense protection with dependable interconnection and backup power, without needing extra smart technology or a complex setup.

The First Alert 9120B is a solid choice for those looking to protect their home with interconnected smoke detectors. It uses hardwired power with a battery backup, so it keeps working even during power outages—a crucial feature for reliable safety. These detectors use ionization sensors, which are good at detecting fast, flaming fires quickly, though they may be less sensitive to slow-smoldering fires compared to photoelectric types.

You can link multiple alarms together, ensuring that if one detects smoke, all alarms sound, which helps alert everyone in the house no matter where they are. Installation is straightforward with included mounting hardware and tamper-resistant brackets, but since it’s hardwired, professional help may be needed if you’re not comfortable with wiring. Maintenance is simple thanks to the single test and silence button and easy access to the battery compartment.

These alarms don’t have advanced smart features like mobile alerts or integration with other smart home devices, which might be a downside if you want more modern connectivity. This 3-pack offers dependable, easy-to-use smoke detection with strong interconnect capabilities and backup power, perfect for homeowners prioritizing basic, proven safety without extra tech bells and whistles.