10 Best Smoke Detector Carbon Monoxide Detectors Combo 2025 in the United States

The Kidde Smoke & Carbon Monoxide Detector 2-pack is a practical choice if you're looking for an easy-to-use device that covers both smoke and carbon monoxide detection. It combines photoelectric and electrochemical sensors, which helps it detect smoke from fires and dangerous carbon monoxide gas effectively. One big plus is its 10-year battery life — you won't need to worry about changing batteries or annoying low-battery chirps for a decade, which also saves money over time. Installation is simple since it’s battery powered and wireless; just mount it on the ceiling and click it into place. It has clear LED lights to show its status, so you can easily see if everything's normal, if there's a problem, or if an alarm is sounding.

The 85-decibel alarm is loud enough to alert you even if you’re in another room. It also features a test and hush button, handy for checking the alarm works or silencing false alarms, which are less common thanks to its improved sensing technology that reduces alerts from normal cooking smoke. However, it doesn't support interconnectivity, so multiple alarms won't communicate with each other, which might be a drawback if you want whole-home coverage with linked alerts. Its operating conditions are quite standard, suitable for typical home environments.

This detector is ideal for homeowners who want a reliable, low-maintenance, combo smoke and CO alarm without complicated wiring or smart home features. It has a solid warranty and customer feedback supports its dependable performance, though after 10 years, the entire unit needs replacing, not just the battery.

The First Alert SMCO100 is a battery-operated combo alarm that protects against both smoke and carbon monoxide, making it a practical choice for home safety. It uses photoelectric sensors, which are especially good at detecting smoldering fires and reducing false alarms from cooking. This means fewer annoying nuisance alarms compared to traditional models.

Since it runs on 2 included AA batteries, installation is simple and you don’t have to worry about wiring, though you will need to replace batteries periodically. The alarm includes a test/silence button for easy checks and temporarily silencing false alerts. It also has an end-of-life warning that notifies you when it’s time to replace the unit, helping to ensure ongoing protection. The 3-pack offers good value for covering multiple rooms or floors. However, since these smoke/CO detectors are not interconnected, alarms won’t sound simultaneously throughout the house if one detects danger, which could be a drawback for larger homes.

This First Alert model provides a reliable, user-friendly option for those seeking straightforward, battery-powered smoke and carbon monoxide detection without extra complexity.

The Kidde Smoke Detector & Carbon Monoxide Detector Combo is a solid choice if you're looking for a single device that covers both smoke and CO detection. It uses a photoelectric sensor to catch slow, smoldering fires and an electrochemical sensor to detect carbon monoxide gas, which means it handles two important risks effectively. The device is powered by a long-lasting lithium battery that lasts up to 10 years, so you won’t have to worry about frequent battery changes or power outages affecting its operation. The 85-decibel alarm is loud enough to alert you clearly in case of danger, and a red LED light indicates when smoke or CO is detected. The test-hush button is a convenient feature for silencing false alarms, like those from cooking steam, without disabling the unit.

Installation is straightforward with an automatic alarm activation once mounted—no switches or pull tabs to fuss with. The device also has a chirp alert to let you know when it’s time to replace the alarm after its lifespan. However, this model is battery-operated only and does not support interconnectivity with other alarms, so it won’t sync with additional units around your home. It also has a limited temperature and humidity range suitable for typical indoor environments but may not perform as well in extreme conditions.

Since it is discontinued by the manufacturer, future replacements might require switching to a newer model. If you want a dependable, low-maintenance smoke and CO alarm combo for everyday home use without needing networked alarms, this Kidde model offers a reliable and easy-to-use solution.