Head-to-head · Best Carbon Monoxide Detectors

First Alert CO710 Carbon Monoxide Alarm vs First Alert SC5 Smart Smoke and Carbon Monoxide Alarm

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

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The short answer

First Alert SC5 Smart Smoke and Carbon Monoxide Alarm comes out ahead by a clear margin (4.0 vs 4.5). The gap is mostly about Smart home users wanting integration — read the strengths below before deciding.

Ranked #4 in Best Carbon Monoxide Detectors

First Alert CO710 Carbon Monoxide Alarm

4.0

1 sourceall derived$50as of Aug 1

A sealed 10-year battery is the whole argument for the CO710: nothing to replace, nothing to buy again, and an end-of-life warning when the decade is up. An electrochemical sensor drives an 85-decibel alarm, and a backlit digital display shows the current carbon monoxide reading alongside room temperature. It mounts on a wall or sits on a shelf, and it is small and light enough that owners move it between homes and hotel rooms. There is no app and no hub.

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

$50 · Buy at firstalertstore.com Full review →

Higher ratedRanked #2 in Best Carbon Monoxide Detectors

First Alert SC5 Smart Smoke and Carbon Monoxide Alarm

4.5

2 sources1 derived$129.96as of Aug 1

The First Alert SC5 Smart Smoke and Carbon Monoxide Alarm wraps app-based control in a modern design that adds up to better home safety. Bob Vila reviewers liked the simple installation, the one-button silence feature, and Google Home integration. Isaac from Smart Home Explained rated the build quality above the competition and found app setup smooth. Against that: the $130 price point and interconnect features that only work with a limited set of brands. It suits people who want smart home integration and a better user experience than traditional detectors give, though anyone with existing non-First Alert systems won't get full network coverage.

Strengths

— Easy installation with pre-installed batteries and voice-guided setup
— One-button silence feature improves user experience during false alarms
— Integrates seamlessly with Google Home smart home ecosystem

Watch-outs

— Price is significantly higher than standard alarms at around $130 per unit
— Limited interconnect compatibility with other brands like Kidde and Nest Protect

$129.96 · Check Price on Amazon Full review →

Derived means the reviewer published no score, so one was inferred from their written verdict. Everything else is a number the publisher printed. How we rank.

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.

First Alert SC5 Smart Smoke and Carbon Monoxide Alarm

The SC5 Smart Alarm outperforms the CO710 in smart home integration with Google Home compatibility and app-based testing, while the CO710 lacks smart connectivity. Compared to the basic First Alert detector, the SC5 offers superior user experience with one-button silence and voice alerts, though it comes at a significantly higher price point.

Specs side-by-side

Spec	First Alert CO710 Carbon Monoxide Alarm	First Alert SC5 Smart Smoke and Carbon Monoxide Alarm
Detection Type	Electrochemical sensor	Smart Smoke and CO Alarm
Power Source	Battery operated	Built-in lithium backup battery
Battery Life	10 years	10-year sealed lithium battery
Display	Digital	LED light ring
Alarm Thresholds	85 dB	—
Features	Carbon monoxide detection	App-based testing, voice alerts, one-button silence
Connectivity	None	Google Home compatible
Dimensions	—	5.75"D x 1.6"W x 5.75"H

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