First Alert SC5 Hardwire Smart Smoke & CO Alarm vs X-Sense Wi-Fi Carbon Monoxide Alarm comparison

Data from Amazon and official First Alert and X-Sense sites.

2026 verdict

Choosing between whole-house hazard coverage and a dedicated CO gadget, the First Alert SC5 Hardwire Smart Smoke & CO Alarm takes this smoke and CO alarm matchup by combining smoke and carbon monoxide sensing in one hardwired unit, backed by Google Home integration, steam-check tuning, and a 10-year warranty. The X-Sense Wi-Fi Carbon Monoxide Alarm brings a friendlier price, higher owner rating, and a large LCD screen showing live CO readings plus a built-in light, but it detects carbon monoxide only and has no smart home integrations at all. The two also differ in setup: the SC5 Hardwire runs on mains power with a battery backup, while the freestanding X-Sense unit runs entirely on a replaceable battery and needs no wiring or wall mount. Households wanting one hardwired alarm that covers both smoke and CO with app alerts should choose the First Alert SC5 Hardwire Smart Smoke & CO Alarm, while anyone who already has smoke coverage and just needs an affordable standalone CO monitor for a boiler room or garage should get the X-Sense Wi-Fi Carbon Monoxide Alarm.

Winner

First Alert

First Alert SC5 Hardwire Smart Smoke & CO Alarm

C$169.99

Buy on Amazon Canada

X-Sense

X-Sense Wi-Fi Carbon Monoxide Alarm

Price unavailable right now

Buy on Amazon UK

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Feature	First Alert SC5 Hardwire Smart Smoke & CO Alarm	X-Sense Wi-Fi Carbon Monoxide Alarm	Winner
Rating	3.4	4.6	X-Sense Wi-Fi Carbon Monoxide Alarm
Warranty	10 years	5 years	First Alert SC5 Hardwire Smart Smoke & CO Alarm
Screen	NO	YES	X-Sense Wi-Fi Carbon Monoxide Alarm
Sensors	Smoke, CO	CO	First Alert SC5 Hardwire Smart Smoke & CO Alarm
Alerts	Fire Alerts, CO Alerts, Low Battery Alerts	CO Alerts, Low Battery Alerts	First Alert SC5 Hardwire Smart Smoke & CO Alarm
Built-in Light	NO	YES	X-Sense Wi-Fi Carbon Monoxide Alarm
Steam Check	YES	NO	First Alert SC5 Hardwire Smart Smoke & CO Alarm
Connectivity	2.4 GHz WiFi	2.4 GHz WiFi	Tie
Integrations	Google Home	Home Assistant	Tie
Built-in Siren	YES	YES	Tie
Tests Itself	NO	NO	Tie
Pathlight	NO	NO	Tie

Winner

First Alert

First Alert SC5 Hardwire Smart Smoke & CO Alarm

C$169.99

Buy on Amazon Canada

+ Warranty: 10 years
+ Sensors: Smoke, CO
+ Alerts: Fire Alerts, CO Alerts, Low Battery Alerts
- Rating: 3.4 vs 4.6
- Screen: NO vs YES

X-Sense

X-Sense Wi-Fi Carbon Monoxide Alarm

Price unavailable right now

Buy on Amazon UK

+ Rating: 4.6
+ Screen: YES
+ Built-in Light: YES
- Warranty: 5 years vs 10 years
- Sensors: CO vs Smoke, CO

Frequently Asked Questions

Which is better overall: the First Alert SC5 Hardwire Smart Smoke & CO Alarm or the X-Sense Wi-Fi Carbon Monoxide Alarm?

The First Alert SC5 Hardwire Smart Smoke & CO Alarm wins overall, since it detects both smoke and carbon monoxide, integrates with Google Home, and carries a longer warranty. The X-Sense Wi-Fi Carbon Monoxide Alarm's strengths are its price, rating, and LCD screen.

What is the biggest difference between these two alarms?

Hazard coverage. The First Alert SC5 Hardwire Smart Smoke & CO Alarm detects smoke and carbon monoxide together and is hardwired with a battery backup, while the X-Sense Wi-Fi Carbon Monoxide Alarm is a battery-only, carbon-monoxide-only device with no smoke sensor.

Does the X-Sense Wi-Fi Carbon Monoxide Alarm work with Google Home or Alexa?

No. It has no smart home platform integrations at all and connects only to its own app over WiFi. The First Alert SC5 Hardwire Smart Smoke & CO Alarm integrates with Google Home.

Which alarm shows a live CO reading on a screen?

The X-Sense Wi-Fi Carbon Monoxide Alarm has a large LCD screen displaying the live carbon monoxide level. The First Alert SC5 Hardwire Smart Smoke & CO Alarm has no display.

Who should buy the First Alert SC5 Hardwire Smart Smoke & CO Alarm?

Homeowners with existing alarm wiring who want a single hardwired device covering both smoke and carbon monoxide, with Google Home alerts and steam-check false-alarm filtering.

Who should buy the X-Sense Wi-Fi Carbon Monoxide Alarm?

Anyone who already has smoke detection covered and just needs an affordable, freestanding carbon monoxide monitor, for example near a gas boiler or wood stove, without any smart home integration requirement.

Full comparison table

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