Head-to-head · Best Carbon Monoxide Detectors

First Alert CO710 Carbon Monoxide Alarm vs Kidde Hardwired Smart Smoke and Carbon Monoxide Detector

Which is the better buy? Side-by-side on rating, price, strengths, and watch-outs — with the published ratings we averaged to get there.

The short answer

First Alert CO710 Carbon Monoxide Alarm comes out ahead by a narrow margin (4.5 vs 4.4). The gap is mostly about Travelers and low-maintenance users — read the strengths below before deciding.

Higher ratedRanked #1 in Best Carbon Monoxide Detectors

First Alert CO710 Carbon Monoxide Alarm

4.5

$46

The First Alert CO710 Carbon Monoxide Alarm features a 10-year sealed battery that eliminates the need for battery replacements, according to reviewers. Users praise its digital display and ease of installation. Consumer Reports recommends it as a reliable option for home safety. Some users note that testing requires firm pressing, and there's debate about optimal placement. This alarm is ideal for those seeking a low-maintenance, long-lasting CO detector.

Strengths

— 10-year sealed battery eliminates need for battery replacement
— Digital display shows carbon monoxide levels clearly
— Easy to install and portable for travel use

Watch-outs

— Requires firm pressing to test function
— Some users report conflicting information about optimal placement

$46 · Check Price on Amazon Full review →

Ranked #2 in Best Carbon Monoxide Detectors

Kidde Hardwired Smart Smoke and Carbon Monoxide Detector

4.4

$75

The Kidde Hardwired Smart Smoke and Carbon Monoxide Detector offers comprehensive safety with a 10-year battery life and advanced detection technology that's 25% faster and 3X more precise than average smoke alarms. TechHive reviewer Christopher Null praised its reliable performance and interconnect capabilities but noted it lacks smart home integration and is pricey for a non-smart model. The unit includes voice alerts and can interconnect up to 24 devices, though installation requires basic wiring knowledge. Best for users prioritizing traditional safety features over smart connectivity.

Strengths

— 10-year lifespan with non-removable battery
— Fast smoke detection (25% faster than average)
— 3X more precise smoke detection than average

Watch-outs

— No smart home connectivity or Wi-Fi features
— Busy design that juts out 2 inches from wall/ceiling
— High price for model without smart features

$75 · Check Price on Amazon Full review →

How they stack up

First Alert CO710 Carbon Monoxide Alarm

The CO710 excels with its 10-year sealed battery, unlike the Klein ET110 which requires periodic calibration and the SC5 which needs regular battery replacements. While the SC5 offers smart features and the basic First Alert detector provides dual protection, the CO710 stands out for its portability and travel-friendly design, making it ideal for temporary living situations.

Kidde Hardwired Smart Smoke and Carbon Monoxide Detector

The Kidde hardwired model surpasses the SC5 in detection speed and precision, offering 25% faster smoke detection and 3X more accurate readings, while the SC5 lacks these performance advantages. Unlike the basic First Alert detector, it provides advanced interconnect features for up to 24 devices, though it lacks smart home integration. The Klein ET110 offers more professional-grade features, but the Kidde model provides the most robust traditional safety features.

Specs side-by-side

Spec	First Alert CO710 Carbon Monoxide Alarm	Kidde Hardwired Smart Smoke and Carbon Monoxide Detector
Detection Type	Electrochemical sensor	Dual Sensor
Power Source	Battery operated	Hardwired
Battery Life	10 years	10 years
Display	Digital	LED indicator
Alarm Thresholds	85 dB	—
Features	Carbon monoxide detection	Voice alerts, false alarm reduction
Connectivity	—	Wi-Fi, Ring App, Amazon Alexa, Google Home

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