Head-to-head · Best Carbon Monoxide Detectors

First Alert SC5 Smart Smoke and 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

Kidde Hardwired Smart Smoke and Carbon Monoxide Detector comes out ahead by a clear margin (4.1 vs 4.4). The gap is mostly about Users prioritizing traditional safety — read the strengths below before deciding.

Ranked #4 in Best Carbon Monoxide Detectors

First Alert SC5 Smart Smoke and Carbon Monoxide Alarm

4.1

$111

The First Alert SC5 Smart Smoke and Carbon Monoxide Alarm offers a modern design and app-based control that enhances home safety. Bob Vila reviewers praised its simple installation, one-button silence feature, and Google Home integration. Isaac from Smart Home Explained noted the device's superior build quality and smooth app setup process. However, the $130 price point and limited brand compatibility for interconnect features are drawbacks. This alarm suits users seeking smart home integration and improved user experience over traditional detectors, but those with existing non-First Alert systems may miss out on 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

$111 · Check Price on Amazon Full review →

Higher ratedRanked #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 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.

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 SC5 Smart Smoke and Carbon Monoxide Alarm	Kidde Hardwired Smart Smoke and Carbon Monoxide Detector
Detection Type	Smart Smoke and CO Alarm	Dual Sensor
Power Source	Built-in lithium backup battery	Hardwired
Battery Life	10-year sealed lithium battery	10 years
Connectivity	Google Home compatible	Wi-Fi, Ring App, Amazon Alexa, Google Home
Display	LED light ring	LED indicator
Alarm Thresholds	70 PPM CO concentration	—
Features	App-based testing, voice alerts, one-button silence	Voice alerts, false alarm reduction

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