10 Best Co Smoke Detector Combo 2025 in the United States

The First Alert SMICO100-AC is a 6-pack of combination smoke and carbon monoxide alarms designed for home safety. It uses ionization sensors, which are effective at quickly detecting fast-flaming fires but can be more prone to occasional false alarms from cooking smoke. This model benefits from First Alert's Precision Detection technology, which helps reduce those nuisance alarms, making it more reliable in kitchens or near cooking areas. The alarms are hardwired with a battery backup, ensuring they stay powered even during outages, which is essential for continuous protection.

Another helpful feature is its ability to interconnect with most First Alert and BRK alarms; when one alarm detects a problem, all connected alarms sound together for quicker alerts throughout the home. The latching alarm indicator visually shows which unit triggered the alert or has a low battery, making it easier to identify the source. Installation is simplified by a mounting bracket that allows some rotation for proper alignment. The alarms come with included 9V batteries and promise long-term safety, supported by a brand with a strong reputation in home security.

One limitation is that ionization sensors may not detect smoldering fires as quickly as photoelectric types, so those seeking broader fire detection might consider photoelectric or dual-sensor alarms. Additionally, while the alarms interconnect, this functionality only works fully within the same brand ecosystem. For users wanting smart features or a digital display, this model lacks those, maintaining a straightforward design without advanced connectivity like smartphone alerts. This 6-pack is well suited for homeowners looking to protect multiple rooms affordably with reliable, easy-to-install hardwired detectors that cover both smoke and carbon monoxide risks.

The Kidde Hardwired Smoke & Carbon Monoxide Detector is a solid choice for anyone wanting dependable combined protection against both smoke and carbon monoxide in one device. It uses photoelectric and electrochemical sensors, which are effective for detecting smoke and CO respectively. Powered by hardwired 120V AC with a 10-year lithium-ion battery backup, this unit offers continuous monitoring without the hassle of frequent battery changes—meaning it’s low-maintenance and reliable. Its voice alerts clearly announce “Fire!” or “Warning! Carbon Monoxide!” helping you quickly understand the threat, which is especially useful for all household members, including children or older adults.

The alarms are interconnectable, so if one detects danger, all alarms in the home will sound, increasing safety by ensuring you hear alerts no matter where you are. LED indicators provide easy-to-understand status updates: green for normal, amber for errors, and red when an alarm is triggered. The detector is designed to reduce false alarms often caused by cooking, which can be a common annoyance. Additionally, a self-testing feature helps keep the alarm working properly, though a weekly manual test is still recommended. The 10-year warranty aligns with the expected lifespan, indicating durability and manufacturer confidence.

This model does not include advanced smart features like app connectivity or remote alerts, which might be a consideration if you want modern smart home integration. Also, installation requires wiring into your home’s electrical system, so it’s best suited for those comfortable with or able to hire professional installation. This Kidde detector fits well for households wanting a reliable, easy-to-understand, low-maintenance smoke and CO alarm combo, especially where long battery life and clear voice alerts are priorities.

The FIRST ALERT BRK SC9120FF is a reliable hardwired smoke and carbon monoxide detector that features a battery backup to stay operational during power outages. This combination unit uses dual sensors: an ionization sensor for detecting fast-flaming fires and an electrochemical sensor for sensing carbon monoxide, providing solid protection against this odorless gas. It emits a loud 85-decibel alarm with indicator lights that clearly show whether smoke or carbon monoxide is detected.

This detector can be interconnected with other compatible First Alert or BRK alarms, so if one detects danger, all connected alarms sound simultaneously, enhancing safety throughout the home. Installation is straightforward with tamper-resistant, universal mounting brackets and a side-load battery compartment for easy backup battery replacement. Additionally, the unit is backed by a 10-year limited warranty, aligning with the typical lifespan of smoke and CO alarms, minimizing concerns about replacement for a decade.

Although it lacks smart features such as app notifications or voice alerts, its proven reliability and simple operation with a single test/silence button make it suitable for families seeking trusted, hassle-free protection. Since the alarm is not wireless, it requires professional or careful installation to be hardwired properly. This detector is a dependable, easy-to-use combination alarm that performs well in standard home safety setups.