Smart smoke and CO detectors can send alerts beyond the alarm itself, but the right choice depends on your wiring, app preferences, and need for whole-home coverage. My best overall pick is the First Alert SC5 Hardwired Smart Smoke and Carbon Monoxide Alarm for buyers seeking a connected smoke and CO alarm that works with existing hardwired setups. The Kidde Smart Smoke and CO Detector with Ring suits homes already using Ring, while the X-Sense SC06-W 6-Pack stands out for buyers prioritizing interconnected coverage across several rooms. The tradeoffs include hardwired installation versus battery convenience, single alarms versus multi-unit systems, and app features versus simpler operation. Read on for the full comparison, ranking logic, and guidance on matching an alarm to your home.
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Key Takeaways
- The First Alert SC5 Hardwired ranks first for combining smoke and CO detection with smart alerts in a hardwired format; the battery SC5 is the more flexible choice where wiring is unavailable.
- Kidde models with Ring are the clearest fit for households already using Ring, while buyers outside that ecosystem should compare app compatibility before choosing.
- X-Sense six-packs emphasize interconnected coverage across multiple locations, making them more relevant to whole-home planning than a single replacement alarm.
- Battery and hardwired options solve different installation problems: backup batteries can keep compatible hardwired alarms running during outages, while battery-only models avoid wiring changes.
- Not every listed alarm offers the same kind of smart functionality. Some focus on app alerts or a gateway, while other options prioritize basic detection, long-life battery operation, or interconnection.
| Kidde Smart Smoke Detector with Ring, AA Battery, RGSDR-RW | ![]() | Best for Ring Households | Power: 2 AA alkaline batteries, included | Detection: Smoke | Connectivity: Wire-free interconnectivity with other Kidde alarms | VIEW ON AMAZON | See Our Full Breakdown |
| Kidde Smart Carbon Monoxide Detector with Indoor Air Quality Monitoring | ![]() | Best for Air Quality Insights | Model: COPDLQW | Power: 120V plug-in with two AA backup batteries | Wi-Fi: 2.4 GHz | VIEW ON AMAZON | See Our Full Breakdown |
| First Alert SC5 Hardwired Smart Smoke and Carbon Monoxide Alarm | ![]() | Best for Hardwired Replacement | Alarm types: Smoke and carbon monoxide | Power: Hardwired with battery backup | Phone alerts: First Alert app | VIEW ON AMAZON | See Our Full Breakdown |
| HEIMAN Smart Carbon Monoxide Detector 3-Pack with Gateway | ![]() | Best for Multi-Room CO Coverage | Model: C1-R | Set contents: Three CO detectors and one gateway | Sensor: FIGARO TGS5141 electrochemical sensor | VIEW ON AMAZON | See Our Full Breakdown |
| Kidde Smart Smoke and Carbon Monoxide Detector with Ring App, Battery Powered | ![]() | Best Battery-Powered Combo | Detection: Smoke and carbon monoxide | Power: Two AA alkaline batteries, included | Connectivity: Ring app notifications and wire-free interconnectivity with Kidde alarms | VIEW ON AMAZON | See Our Full Breakdown |
| First Alert SC5 Battery Smart Smoke and Carbon Monoxide Alarm | ![]() | Best for App Alerts Without Hardwiring | Brand: First Alert | Model: SMCO600NV | Alarm type: Combination smoke and carbon monoxide alarm | VIEW ON AMAZON | See Our Full Breakdown |
| First Alert Hardwired Smoke and Carbon Monoxide Alarm | ![]() | Best for Replacing a Hardwired Alarm | Alarm types: Smoke and carbon monoxide | Power: Hardwired with battery backup | Interconnectivity: Compatible with most First Alert and BRK alarms | VIEW ON AMAZON | See Our Full Breakdown |
| X-Sense SC06-W 6-Pack Interconnected Smoke and Carbon Monoxide Detectors | ![]() | Best for Whole-Home Wireless Coverage | Brand: X-Sense | Model: SC06-W | Quantity: 6 alarms | VIEW ON AMAZON | See Our Full Breakdown |
| First Alert 10-Year Battery Smoke and Carbon Monoxide Alarm | ![]() | Best for Ring-Connected Battery Backup | Brand: First Alert | Model: SMCO410 | Detection: Smoke and carbon monoxide | VIEW ON AMAZON | See Our Full Breakdown |
| Kidde Smart Smoke Detector with Ring, Hardwired and AA Battery Backup, RGSAR-RW | ![]() | Best for Alexa-Connected Hardwired Smoke Alerts | Model: RGSAR-RW | Detection: Smoke | Power: Hardwired with AA battery backup | VIEW ON AMAZON | See Our Full Breakdown |
| X-Sense SC07 Smoke and Carbon Monoxide Detector, 1-Pack | ![]() | Best for Simple, Long-Life Protection | Model: SC07 | Pack size: 1 alarm | Smoke sensor: Photoelectric | VIEW ON AMAZON | See Our Full Breakdown |
| Kidde Hardwired Smart Smoke and Carbon Monoxide Detector with App Alerts and Battery Backup | ![]() | Best for Phone-Based Hush Control | Detection: Smoke and carbon monoxide | Power: Hardwired with AA battery backup | Connectivity: 2.4 GHz Wi-Fi | VIEW ON AMAZON | See Our Full Breakdown |
| X-Sense SC07-W Interconnected Smoke and Carbon Monoxide Detector, 6-Pack | ![]() | Best for Wireless Whole-Home Alerts | Model: SC07-W | Pack size: 6 alarms | Detection: Photoelectric smoke and electrochemical carbon monoxide | VIEW ON AMAZON | See Our Full Breakdown |
| Kidde Smart Smoke and CO Detector with Ring, Hardwired with AA Battery Backup | ![]() | Best for Ring and Alexa Homes | Detection: Smoke and carbon monoxide | Power: Hardwired with AA battery backup | App alerts: Ring app notifications for smoke, CO, and low battery | VIEW ON AMAZON | See Our Full Breakdown |
| smart smoke and co detector | Power | Detection | Model | Connectivity |
|---|---|---|---|---|
| Kidde Smart Smoke Detector wit | 2 AA alkaline batteries, included | Smoke | — | Wire-free interconnectivity with other Kidde alarms |
| Kidde Smart Carbon Monoxide De | 120V plug-in with two AA backup batteries | — | COPDLQW | — |
| First Alert SC5 Hardwired Smar | Hardwired with battery backup | — | — | — |
| HEIMAN Smart Carbon Monoxide D | Battery operated; batteries included | — | C1-R | — |
| Kidde Smart Smoke and Carbon M | Two AA alkaline batteries, included | Smoke and carbon monoxide | — | Ring app notifications and wire-free interconnectivity with Kidde alarms |
| First Alert SC5 Battery Smart | 3V CR123A lithium batteries | — | SMCO600NV | — |
| First Alert Hardwired Smoke an | Hardwired with battery backup | — | — | — |
| X-Sense SC06-W 6-Pack Intercon | — | Smoke and carbon monoxide | SC06-W | Wireless interconnection; no Wi-Fi or base station connection |
| First Alert 10-Year Battery Sm | — | Smoke and carbon monoxide | SMCO410 | Z-Wave Plus |
| Kidde Smart Smoke Detector wit | Hardwired with AA battery backup | Smoke | RGSAR-RW | — |
| X-Sense SC07 Smoke and Carbon | — | — | SC07 | Standalone; no wireless interconnection, Wi-Fi, or base station connection |
| Kidde Hardwired Smart Smoke an | Hardwired with AA battery backup | Smoke and carbon monoxide | — | 2.4 GHz Wi-Fi |
| X-Sense SC07-W Interconnected | — | Photoelectric smoke and electrochemical carbon monoxide | SC07-W | No Wi-Fi or base station connection |
| Kidde Smart Smoke and CO Detec | Hardwired with AA battery backup | Smoke and carbon monoxide | — | — |
More Details on Our Top Picks
Kidde Smart Smoke Detector with Ring, AA Battery, RGSDR-RW
For a home already using Ring, this Kidde adds smoke and low-battery alerts in the same app, with no subscription needed for those basic notifications. Its AA battery power avoids wiring, and wireless links to other Kidde alarms can spread an alert beyond the room where smoke is detected. Compared with the Kidde Smart Smoke and Carbon Monoxide Detector with Ring App, this model detects smoke only, so it cannot cover carbon monoxide on its own. Enhanced sensing is designed to reduce cooking-related false alarms, a useful feature near kitchens, though it does not remove the need to place alarms thoughtfully. The tradeoff is ongoing battery replacement; 24/7 monitoring also costs extra. I’d choose it for Ring users who want a straightforward smoke alarm, not an all-in-one smoke and CO option.
Pros:- Ring app smoke and low-battery alerts are available without a required subscription
- AA battery power avoids hardwired installation
- Wirelessly interconnects with other Kidde alarms
- Enhanced sensing is designed to reduce cooking-related false alarms
Cons:- Detects smoke only, unlike the Ring-connected Kidde smoke and CO model
- AA batteries need periodic replacement
- 24/7 smoke monitoring requires an optional paid subscription
Best for: Ring users who want app alerts from a battery-powered smoke alarm without adding wiring
Not ideal for: Buyers seeking carbon monoxide detection in the same unit or 24/7 monitoring without a subscription
- Power:2 AA alkaline batteries, included
- Detection:Smoke
- Connectivity:Wire-free interconnectivity with other Kidde alarms
- App alerts:Ring app smoke and low-battery notifications
- Voice assistant:Alexa notifications
- Certification:UL 217 and FCC
- Optional monitoring:24/7 smoke monitoring available by subscription
Our verdict“Choose this if you use Ring and need an easy-to-place smart smoke alarm; choose the paired Kidde smoke and CO model if you also need CO detection.”
Kidde Smart Carbon Monoxide Detector with Indoor Air Quality Monitoring
This Kidde is the lineup’s information-focused pick: alongside CO detection, it reports humidity, temperature, and TVOC, giving connected households a broader view of indoor conditions than the smoke-and-CO alarms here. Its plug-in format keeps it powered from a wall outlet, while two AA batteries provide backup if power fails. The detector can flag low CO levels from 30–70 ppm and uses a separate alarm pattern for dangerous levels, which offers more context than a basic CO alarm. Compared with the HEIMAN Smart Carbon Monoxide Detector 3-Pack, it adds environmental readings and Alexa and Google Home compatibility, but covers one outlet location rather than multiple rooms. App notifications do not require a subscription; advanced air quality insights do, and setup requires 2.4 GHz Wi-Fi.
Pros:- Monitors humidity, temperature, and TVOC in addition to CO
- Provides low-level CO alerts and a distinct pattern for dangerous levels
- App notifications are available without a required subscription
- AA battery backup and Alexa and Google Home compatibility
Cons:- Requires a 2.4 GHz Wi-Fi network for app connectivity
- Advanced air quality insights require an optional subscription
- A single plug-in detector offers less room coverage than the HEIMAN three-pack
Best for: Smart home users who want CO alerts plus humidity, temperature, and TVOC readings in a frequently occupied room
Not ideal for: Households needing multiple room placements, lacking 2.4 GHz Wi-Fi, or unwilling to use a plug-in outlet
- Model:COPDLQW
- Power:120V plug-in with two AA backup batteries
- Wi-Fi:2.4 GHz
- Alarm volume:85 dB
- Low-level CO alerts:30–70 ppm
- Air quality readings:Humidity, temperature, and TVOC
- Smart home compatibility:Amazon Alexa and Google Home
- Standards:UL 2034, 5th Edition; ETL Listed
- Warranty:10-year limited warranty
Our verdict“Pick this for one connected room where indoor air readings matter alongside CO alerts, and choose a multi-detector set for broader coverage.”
First Alert SC5 Hardwired Smart Smoke and Carbon Monoxide Alarm
For a home with existing alarm wiring, the SC5 combines smoke and CO detection with app alerts and backup power in one replacement unit. Its voice alerts identify the danger type and location, helping occupants make sense of an alarm that might otherwise sound like every other alarm in the house. Compatible alarms can interconnect and sound together, while Precision Detection Technology is designed to reduce nuisance alarms. The Quick Connect Plug simplifies installation or replacement without rewiring, but this remains a hardwired product; it is not as flexible to place as the battery-powered Kidde Smart Smoke and Carbon Monoxide Detector with Ring App. First Alert app alerts also tie remote notifications to a separate app ecosystem. This is a stronger fit for a wired home that needs smoke and CO in one unit than for renters or anyone starting without alarm wiring.
Pros:- Detects both smoke and carbon monoxide
- Voice alerts identify the type and location of danger
- Battery backup maintains operation during power outages
- Compatible alarms can interconnect, and the Quick Connect Plug avoids rewiring for replacement
Cons:- Requires a hardwired alarm connection
- Phone alerts require the First Alert app
- Interconnection depends on compatible alarms
Best for: Homeowners replacing a hardwired alarm who want smoke, CO, voice alerts, and phone notifications
Not ideal for: Renters or households without compatible hardwired alarm connections
- Alarm types:Smoke and carbon monoxide
- Power:Hardwired with battery backup
- Phone alerts:First Alert app
- Interconnectivity:Interconnects with compatible alarms
- Voice alerts:Identifies danger type and location
- Detection technology:Precision Detection Technology
- Installation:Quick Connect Plug; replacement without rewiring
- Compatibility:Compatible with Google’s Nest Protect Alarm
Our verdict“Choose the SC5 for a wired home that needs one connected smoke and CO replacement with spoken location cues.”
HEIMAN Smart Carbon Monoxide Detector 3-Pack with Gateway
The HEIMAN set is built around coverage across three locations: its battery-powered CO detectors interconnect, while the gateway brings alarm alerts and logs to the app. That makes it a better fit for a home that needs several CO points than the single-outlet Kidde Smart Carbon Monoxide Detector with Indoor Air Quality Monitoring. HEIMAN also supports Home Assistant, IFTTT, Google Home, and SmartThings, giving smart home users several integration routes. The tradeoff is a more involved setup: remote alerts depend on the gateway and Wi-Fi, and some integrations may need a compatible hub and configuration. This set detects carbon monoxide only, so it does not replace smoke alarms. Its 10-year detector life and included batteries reduce routine upkeep, but its app and ecosystem advantages matter most to households willing to configure connected devices.
Pros:- Three detectors provide CO coverage in multiple locations
- Interconnected alarms can sound together
- Gateway sends app alerts and keeps alarm logs
- Supports Home Assistant, IFTTT, Google Home, and SmartThings
Cons:- Detects CO only and does not replace smoke alarms
- Remote alerts depend on the gateway and Wi-Fi
- Some smart home integrations may require a compatible hub and setup
Best for: Smart home households that want interconnected CO detectors across several rooms and are comfortable setting up a gateway
Not ideal for: Buyers seeking smoke detection in the same devices or wanting simple app alerts without gateway and Wi-Fi setup
- Model:C1-R
- Set contents:Three CO detectors and one gateway
- Sensor:FIGARO TGS5141 electrochemical sensor
- Interconnect range:Up to 200 m (656 ft)
- Power:Battery operated; batteries included
- Detector dimensions:2.75 × 2.75 × 1.45 in
- Smart home compatibility:Home Assistant, IFTTT, Google Home, and SmartThings
- Certifications:UL 2034 5th Edition; CSFM approved
- Detector life:10 years
Our verdict“Choose this set for connected, multi-room CO coverage if you are prepared to configure the gateway and pair it with separate smoke alarms.”
Kidde Smart Smoke and Carbon Monoxide Detector with Ring App, Battery Powered
This Kidde combines smoke and CO detection with Ring app alerts and wireless links to other Kidde alarms, covering two hazards without requiring a wired installation. Basic alarm and low-battery notifications do not require a subscription, and Alexa-enabled devices can also deliver notifications. Against the smoke-only Kidde Smart Smoke Detector with Ring, AA Battery, RGSDR-RW, this is the more complete choice for a room where both hazards need coverage. It also runs on two AA batteries, so placement is flexible, but battery changes remain part of ownership. Its reduced nuisance alarms compared with earlier Kidde generations may help limit interruptions, though the supplied data does not specify the detection method. Optional 24/7 monitoring carries a separate subscription, so this model’s main appeal is local protection with app connectivity rather than bundled professional monitoring.
Pros:- Detects both smoke and carbon monoxide in one unit
- Ring app alarm and low-battery alerts need no required subscription
- Wire-free interconnectivity can spread alerts through compatible Kidde alarms
- Works with Alexa-enabled devices
Cons:- Two AA batteries require periodic replacement
- 24/7 monitoring requires a separate Ring subscription
- App alerts are tied to the Ring ecosystem
Best for: Ring households that need both smoke and CO detection in a battery-powered, wire-free alarm
Not ideal for: Buyers who prefer hardwired power or want 24/7 monitoring without a separate subscription
- Detection:Smoke and carbon monoxide
- Power:Two AA alkaline batteries, included
- Connectivity:Ring app notifications and wire-free interconnectivity with Kidde alarms
- Alexa compatibility:Notifications from Alexa-enabled devices
- Standards:UL 217 and FCC
- Basic app alerts:Alarm and low-battery notifications without a required subscription
- Optional monitoring:24/7 monitoring available by separate subscription
Our verdict“Choose this over the smoke-only Ring Kidde when you need both smoke and CO coverage without hardwiring.”
First Alert SC5 Battery Smart Smoke and Carbon Monoxide Alarm
The First Alert SC5 Battery suits buyers who want phone alerts and voice guidance without connecting an alarm to household wiring. It detects both smoke and carbon monoxide, and its voice alerts identify the hazard and its location, which can help people react faster when several alarms are linked. Compared with the X-Sense SC06-W 6-Pack, this is a single app-connected alarm rather than a wireless network of six units; the X-Sense covers more rooms but does not connect to Wi-Fi. The SC5 also reports low battery and uses sensing designed to reduce nuisance alarms. Its main tradeoff is the CR123A battery power: buyers need to manage battery replacement, and this one-alarm package may not suit someone outfitting a whole home at once.
Pros:- Detects both smoke and carbon monoxide
- App alerts include danger notifications and low-battery notices
- Voice alerts identify the hazard and its location
- Compatible alarms can sound together
Cons:- Uses replaceable CR123A lithium batteries rather than a sealed 10-year battery
- Sold as one alarm, so whole-home coverage requires additional units
- Smart notifications depend on the First Alert app
Best for: Homeowners who want app notifications and spoken hazard details in a room without hardwired alarm access
Not ideal for: People outfitting many rooms at once or seeking a multi-alarm pack with sealed 10-year batteries
- Brand:First Alert
- Model:SMCO600NV
- Alarm type:Combination smoke and carbon monoxide alarm
- Power:3V CR123A lithium batteries
- Smart alerts:Phone alerts through the First Alert app
- Interconnection:Compatible alarms sound together
- Pack size:1 alarm
Our verdict“Choose the SC5 Battery if app alerts and spoken hazard details matter more than sealed-battery convenience or multi-room coverage in one package.”
First Alert Hardwired Smoke and Carbon Monoxide Alarm
For a home that already has compatible alarm wiring, this First Alert hardwired combination alarm adds carbon monoxide detection while retaining battery backup for outages. It connects with compatible First Alert and BRK alarms, so an alert can carry through the existing system. Compared with the battery-powered First Alert SC5 Battery, this model fits a wired installation and includes an adjustable mounting bracket, but it does not list the SC5’s app notifications or voice alerts. Its Precision Detection sensing is designed to limit cooking-related nuisance alarms, a practical benefit near kitchens. The tradeoff is installation: buyers need compatible wiring and should not treat this as a simple battery-powered replacement. The latching indicator can help identify which unit sounded after an event, though the supplied details do not specify smart phone connectivity.
Pros:- Combines smoke and carbon monoxide detection
- Battery backup keeps the alarm powered during outages
- Interconnects with compatible First Alert and BRK alarms
- Sensing is designed to reduce cooking nuisance alarms
Cons:- Requires a compatible hardwired installation
- Phone alerts and app connectivity are not listed
- Requires an additional battery source for backup
Best for: Homeowners replacing an existing hardwired alarm who want smoke and CO coverage with backup power
Not ideal for: Renters or people without compatible alarm wiring who need a simple, app-connected battery unit
- Alarm types:Smoke and carbon monoxide
- Power:Hardwired with battery backup
- Interconnectivity:Compatible with most First Alert and BRK alarms
- Nuisance alarm feature:Precision Detection designed to reduce cooking alarms
- Alarm indicator:Latching alarm indicator
- Mount:Adjustable mount bracket
Our verdict“Pick this model when you have compatible wiring and want backed-up, interconnected smoke and CO protection without relying on a smart app.”
X-Sense SC06-W 6-Pack Interconnected Smoke and Carbon Monoxide Detectors
The X-Sense SC06-W 6-Pack is aimed at buyers who want linked alarms across multiple rooms without wiring each unit. When one detects smoke or carbon monoxide, the wireless interconnection makes all units sound, giving this pack a broader home-warning role than the single-alarm First Alert SC5 Battery. Its sealed 10-year batteries reduce routine battery changes, and the alarms are certified to UL 217 and UL 2034. That coverage comes with a clear limitation: this system has no Wi-Fi or base station connection, so it cannot provide the app notifications offered by the SC5. It is also not hardwired, which may make it a poor match for homes that need wired replacements. Buyers get six alarms and mounting hardware, but should check that wireless-only interconnection fits their setup.
Pros:- Six alarms provide multi-room coverage in one set
- Wireless interconnection causes all units to sound when one detects danger
- Sealed 10-year batteries reduce routine battery replacement
- UL 217 and UL 2034 certified
Cons:- No Wi-Fi or base station connection for app alerts
- Not hardwired, so it may not suit wired installations
- Six-unit coverage may be more than needed for smaller homes
Best for: Households adding linked smoke and CO alarms to several rooms without running new wiring
Not ideal for: Buyers who need phone alerts, a Wi-Fi-connected system, or hardwired alarm replacements
- Brand:X-Sense
- Model:SC06-W
- Quantity:6 alarms
- Battery:Sealed lithium battery with 10-year life
- Connectivity:Wireless interconnection; no Wi-Fi or base station connection
- Detection:Smoke and carbon monoxide
- Installation:Not hardwired; wall or ceiling mount
- Certifications:UL 217 and UL 2034
- Included:6 alarms, user manual, 18 screws and anchor plugs
Our verdict“Choose the SC06-W pack for broad, wire-free alarm coverage if app notifications are not part of your requirements.”
First Alert 10-Year Battery Smoke and Carbon Monoxide Alarm
This First Alert 10-Year Battery alarm combines sealed-battery convenience with a route to Ring notifications for buyers who already have compatible Ring Alarm equipment. Its Z-Wave Plus connection can send emergency notifications through a Ring Alarm Base Station when paired with the required Ring system. Compared with the app-connected First Alert SC5 Battery, this model offers a sealed battery rated for up to 10 years, but its connected alerts depend on separate Ring equipment rather than the First Alert app. Smoke and CO detection, an end-of-life warning, and sensing designed to reduce cooking nuisance alarms make it a straightforward replacement option. The tradeoff is compatibility: without the specified Ring Alarm setup and Smoke and CO Listener, buyers should expect a standalone alarm rather than phone-connected protection.
Pros:- Detects both smoke and carbon monoxide
- Sealed battery is designed to last up to 10 years
- Can send notifications through a compatible Ring system
- Includes an end-of-life warning
Cons:- Ring Alarm Base Station and required Ring equipment are needed for connected notifications
- Does not provide connected alerts on its own
- Single alarm package offers no multi-room coverage
Best for: Ring Alarm households seeking a sealed-battery combination alarm that can send notifications through their existing system
Not ideal for: Buyers without compatible Ring equipment or anyone expecting direct Wi-Fi and app alerts from the alarm alone
- Brand:First Alert
- Model:SMCO410
- Detection:Smoke and carbon monoxide
- Battery:Sealed 10-year battery
- Connectivity:Z-Wave Plus
- Compatibility:Ring Alarm Base Station; Ring Alarm or Ring Alarm Pro Security Kit with Alarm Smoke and CO Listener required
- Features:Test/silence button and end-of-life warning
- Pack size:1 alarm
Our verdict“This alarm fits Ring households that value a sealed battery and can meet the system requirements for connected notifications.”
Kidde Smart Smoke Detector with Ring, Hardwired and AA Battery Backup, RGSAR-RW
The Kidde RGSAR-RW focuses on connected smoke warnings for homes with hardwired alarms and Ring equipment. It sends smoke and low-battery alerts through the Ring app without a notification subscription, and it can relay Alexa notifications to compatible devices. That makes it a different choice from the First Alert Hardwired Smoke and Carbon Monoxide Alarm, which detects both smoke and CO but does not list app alerts. The Kidde’s key limitation for this roundup is equally clear: it is a smoke detector only, so it does not replace a combination smoke and carbon monoxide alarm where both hazards need coverage. It includes AA battery backup and connects with other hardwired alarms. Optional 24/7 monitoring requires a separate Ring subscription, and its faster-detection claim is based on internal testing.
Pros:- Ring app smoke and low-battery notifications do not require a subscription
- Hardwired alarms can connect throughout the home
- AA battery backup supports operation during power outages
- Compatible Alexa devices can provide notifications
Cons:- Detects smoke only, not carbon monoxide
- Optional 24/7 monitoring requires a separate Ring subscription
- Ring equipment is needed for Ring app features
Best for: Ring and Alexa households adding app-connected smoke alerts to an existing hardwired alarm setup
Not ideal for: Buyers seeking one device to detect both smoke and carbon monoxide or who lack Ring equipment
- Model:RGSAR-RW
- Detection:Smoke
- Power:Hardwired with AA battery backup
- App:Ring
- Voice assistant compatibility:Alexa-enabled devices
- Certifications:UL 217 and FCC
- Optional monitoring:24/7 smoke monitoring available with a separate Ring subscription
Our verdict“Choose the Kidde RGSAR-RW for app-connected smoke alerts in a Ring and Alexa home, while keeping separate CO protection in place.”
X-Sense SC07 Smoke and Carbon Monoxide Detector, 1-Pack
The X-Sense SC07 suits buyers who want smoke and carbon monoxide coverage without wiring or regular battery changes. Its sealed 10-year battery and wall or ceiling mounting make it a straightforward choice for a room that needs a standalone alarm. It uses photoelectric smoke sensing and an electrochemical CO sensor, and meets UL 217 and UL 2034 standards. Compared with the X-Sense SC07-W 6-Pack, this single alarm does not link with other detectors, so an alert in one room will not make alarms elsewhere sound. It also lacks Wi-Fi and app alerts. That tradeoff keeps the setup simple, but makes it a weaker fit for buyers who want remote notifications or coordinated whole-home alerts.
Pros:- Detects both smoke and carbon monoxide
- Sealed battery is designed to last 10 years
- Mounts on a wall or ceiling without rewiring
- Meets UL 217 and UL 2034 standards
Cons:- Does not wirelessly interconnect with other alarms
- No Wi-Fi, app alerts, or base station support
Best for: Homeowners replacing one alarm who want smoke and CO detection without wiring or battery replacement
Not ideal for: Buyers who need alarms to sound together across rooms or want phone notifications while away
- Model:SC07
- Pack size:1 alarm
- Smoke sensor:Photoelectric
- Carbon monoxide sensor:Electrochemical
- Battery life:Designed for 10 years
- Installation:Wall or ceiling mount; no rewiring required
- Certifications:UL 217 and UL 2034
- Connectivity:Standalone; no wireless interconnection, Wi-Fi, or base station connection
Our verdict“Choose the SC07 for a single location where long-life smoke and CO detection matters more than connected alerts.”
Kidde Hardwired Smart Smoke and Carbon Monoxide Detector with App Alerts and Battery Backup
For buyers who want to manage nuisance alarms from another room, this Kidde hardwired smart detector pairs smoke and CO sensing with phone-based hush control. It connects to 2.4 GHz Wi-Fi and can send mobile alerts for smoke, carbon monoxide, and low batteries; voice alerts also sound locally. Its enhanced sensing is designed to reduce cooking-related alarms, a useful distinction from the basic standalone X-Sense SC07, which has no app or hush feature. The Kidde needs hardwiring and Wi-Fi for its smart functions, and AA batteries provide backup if household power is interrupted. One detector alone does not provide whole-home mobile alerts: that requires adding a Kidde smart alarm. Choose it for connected control at a wired location, with that system requirement in mind.
Pros:- Detects both smoke and carbon monoxide
- Sends mobile alerts for smoke, CO, and low batteries
- Allows false alarms to be hushed from a phone
- Enhanced sensing is designed to reduce cooking-related nuisance alarms
Cons:- Requires hardwiring and 2.4 GHz Wi-Fi for smart features
- Whole-home mobile alerts require an additional Kidde smart alarm
Best for: Homeowners with hardwired alarm locations who want remote alerts and the ability to hush a nuisance alarm by phone
Not ideal for: Renters or buyers without 2.4 GHz Wi-Fi, and households seeking whole-home alerts from a single detector
- Detection:Smoke and carbon monoxide
- Power:Hardwired with AA battery backup
- Connectivity:2.4 GHz Wi-Fi
- Alerts:Voice alerts and mobile notifications
- Phone control:Hush false alarms from a phone
- Sensing:Enhanced sensing designed to reduce cooking-related nuisance alarms
- Certifications:UL 217, UL 2034, and FCC
Our verdict“Pick this Kidde for a hardwired spot where app alerts and remote hush control are priorities.”
X-Sense SC07-W Interconnected Smoke and Carbon Monoxide Detector, 6-Pack
The X-Sense SC07-W 6-Pack is aimed at households that want alarms in several rooms to sound together without running new wiring. Its wireless interconnection can link up to 18 compatible alarms over distances up to 820 feet, giving it a clear coverage advantage over the single, standalone X-Sense SC07. Each alarm detects smoke with a photoelectric sensor and CO with an electrochemical sensor, and the built-in battery is designed to last 10 years. An LCD adds a local display, while UL 217 and UL 2034 standards speak to its listed safety scope. The main tradeoff is that synchronized alarms do not bring phone alerts: this model has no Wi-Fi or base station connection. Its sealed battery also is not designed for replacement, so the alarm must be replaced when its service life ends.
Pros:- Six alarms provide multi-room coverage in one set
- Compatible alarms sound together through wireless interconnection
- Sealed battery is designed to last 10 years
- Includes an LCD and requires no wiring
Cons:- No Wi-Fi, app alerts, or base station connectivity
- Sealed battery is not designed for replacement
- Interconnection requires compatible alarms
Best for: Homeowners covering several rooms who want linked alarms without adding wiring
Not ideal for: People who want app notifications or prefer alarms with replaceable batteries
- Model:SC07-W
- Pack size:6 alarms
- Detection:Photoelectric smoke and electrochemical carbon monoxide
- Battery:Built-in sealed lithium battery, designed for 10 years
- Wireless interconnection range:Up to 820 feet
- Maximum linked alarms:18 compatible alarms
- Installation:Wall or ceiling mount; no wiring required
- Display and standards:LCD; UL 217 and UL 2034
- Connectivity:No Wi-Fi or base station connection
Our verdict“Choose the SC07-W set for linked, multi-room smoke and CO alerts without wiring or phone connectivity.”
Kidde Smart Smoke and CO Detector with Ring, Hardwired with AA Battery Backup
This Kidde detector with Ring makes the most sense for homes already using Ring or Alexa: it sends smoke, CO, and low-battery notifications through the Ring app, and works with Alexa. It can also relay alerts from other hardwired alarms, giving it a broader role than the app-connected Kidde detector that focuses on its own alerts and phone-based hush control. Like that Kidde model, this one is hardwired, has AA battery backup, and uses sensing designed to reduce cooking-related nuisance alarms. Basic notifications do not require a subscription; 24/7 smoke and CO monitoring does. That distinction matters for buyers deciding whether app alerts are enough. The product’s faster-detection claim is based on internal testing, so I would weigh its stated features and Ring integration more heavily than that comparison claim.
Pros:- Detects both smoke and carbon monoxide
- Sends basic smoke, CO, and low-battery alerts through the Ring app without a subscription
- Can relay alerts from other hardwired alarms
- Works with Alexa and uses sensing designed to reduce cooking-related nuisance alarms
Cons:- Requires hardwired installation with AA battery backup
- 24/7 smoke and CO monitoring requires an optional Ring subscription
- Faster-detection claim is based on internal testing
Best for: Households with hardwired alarms that already use Ring or Alexa and want app notifications without a monitoring subscription
Not ideal for: Renters, homes without Ring or Alexa, or buyers who want 24/7 professional monitoring without an added subscription
- Detection:Smoke and carbon monoxide
- Power:Hardwired with AA battery backup
- App alerts:Ring app notifications for smoke, CO, and low battery
- Alexa compatibility:Yes
- Alarm relay:Can relay alerts from other hardwired alarms
- Sensing:Designed to reduce cooking-related nuisance alarms
- Standards:UL 217 and FCC certified
- Optional monitoring:24/7 smoke and CO monitoring with a Ring subscription
Our verdict“Choose this model if your hardwired home already uses Ring or Alexa and you want app alerts without paying for monitoring.”

How We Picked
I ranked these 14 alarms by how directly they meet the promise of smart smoke and CO detection, then weighed practical fit: power source, installation needs, app or gateway setup, interconnection, and whether a product covers smoke, carbon monoxide, or both. For a smart-home buyer, a connected alert is useful only if the device fits the home’s wiring and the household can receive and act on its notifications. I gave more weight to clearly described app-connected smoke-and-CO models than to alarms whose listed strengths center on basic detection or multi-unit coverage.
The ordering reflects use cases rather than a claim that one alarm suits every building. The First Alert SC5 Hardwired leads for buyers with compatible wiring and a need for both detection types; its battery counterpart is a stronger fit where hardwiring is impractical. Ring-compatible Kidde picks rise for existing Ring households, while X-Sense multi-packs earn attention for broader interconnected coverage. Models with narrower functions, an added gateway, or less clearly specified smart integration rank lower for readers seeking one straightforward connected smoke-and-CO solution. Buyers should confirm local code, exact model specifications, and compatibility with their current alarm system before installation.
| smart smoke and co detector | Detection |
|---|---|
| Kidde Smart Smoke Detector wit | Smoke |
| Kidde Smart Carbon Monoxide De | — |
| First Alert SC5 Hardwired Smar | — |
| HEIMAN Smart Carbon Monoxide D | — |
| Kidde Smart Smoke and Carbon M | Smoke and carbon monoxide |
| First Alert SC5 Battery Smart | — |
| First Alert Hardwired Smoke an | — |
| X-Sense SC06-W 6-Pack Intercon | Smoke and carbon monoxide |
| First Alert 10-Year Battery Sm | Smoke and carbon monoxide |
| Kidde Smart Smoke Detector wit | Smoke |
| X-Sense SC07 Smoke and Carbon | — |
| Kidde Hardwired Smart Smoke an | Smoke and carbon monoxide |
| X-Sense SC07-W Interconnected | Photoelectric smoke and electrochemical carbon monoxide |
| Kidde Smart Smoke and CO Detec | Smoke and carbon monoxide |
Factors to Consider When Choosing Smart Smoke And Co Detectors
Before choosing an alarm, I would map the home’s existing wiring, alarm locations, and connected-home setup. Those details often narrow the field faster than a feature list because a smart alarm must fit both the building and the way its residents receive alerts.
Match the Alarm to Your Existing Wiring
Start by checking whether each current alarm is hardwired, battery powered, or part of an interconnected circuit. A hardwired replacement may reduce installation changes, but compatible wiring and model requirements matter; a battery model can be simpler to place yet may not connect to existing alarms. Do not assume two alarms can share a circuit just because their housings look similar. Confirm the manufacturer’s compatibility guidance and any local requirements before replacing a wired unit. If you rent, ask the property manager before modifying fixed wiring. Choosing around the existing setup can prevent a smart upgrade from leaving coverage gaps.
Decide What You Mean by Smart Alerts
“Smart” can refer to phone notifications, an app dashboard, integration with a broader home platform, or communication through a separate gateway. These functions are not interchangeable: an alarm may notify a phone while offering little control over other devices, and a gateway-based system adds another component to configure. Consider who should receive an alert, whether multiple household members need access, and what happens if internet service is interrupted. Read the exact product documentation for connectivity and notification limits instead of relying on the product category name. A familiar ecosystem can make setup easier, but it can also narrow which alarms fit naturally. The best connected option is the one your household can configure and maintain reliably.
Plan Coverage by Room and Floor
Count the locations that need an alarm before deciding between a single unit and a multi-pack. Interconnected alarms can help alerts reach people elsewhere in a home, but check whether the specific models communicate with each other and how they connect. A six-pack is useful only when its devices suit the intended locations and installation type. Avoid replacing several alarms with one smart unit on the assumption that phone alerts provide equivalent local warning throughout the home. Follow placement instructions and applicable safety rules for smoke and carbon monoxide alarms. A simple floor-by-floor plan helps you buy enough compatible devices without overlooking a remote sleeping area.
Choose Smoke, CO, or Combined Detection Deliberately
Some options in this roundup detect both smoke and carbon monoxide, while others are listed for only one hazard. Combined alarms can simplify a location that needs both kinds of protection, though they may not meet every placement need in a home. A dedicated CO detector can suit a buyer adding that function to an existing smoke-alarm setup. Check which hazards each model detects and whether the listing describes any additional air-quality monitoring as a separate feature. Do not treat general air-quality readings as a replacement for a certified smoke or CO alarm. Taking inventory of your existing devices helps reveal whether you need a combined replacement or a targeted addition.
Compare Battery Service and Backup Needs
Battery-powered alarms avoid hardwiring, while hardwired units may include battery backup for outages; these arrangements have different maintenance demands. A long-life battery can reduce routine battery changes, but the whole alarm may still have a defined replacement life. Backup batteries also need attention, so check how the device signals low power and what replacement procedure it requires. Think about whether residents can reach ceiling-mounted alarms safely and who will handle maintenance. Check the replacement interval and end-of-life signals in the product documentation before buying. A convenient power setup matters most when it keeps the alarm working years after installation, not just on day one.
Know When Paying for Connected Features Makes Sense
Connected alerts have the most practical value when someone may be away from home, when residents need notifications in another part of a large home, or when a household already maintains a compatible smart-home system. If everyone is usually home and a local alarm is the main need, a simpler unit may be easier to install and maintain. Compare the full setup, including any gateway, app account, network requirements, and ongoing replacement parts. Ask whether the extra feature changes how quickly someone can respond or simply adds another screen to check. A multi-unit interconnected system can address coverage across rooms in a way a single app-connected alarm cannot. Pay for features that solve a specific household problem, not just because they appear on a specification list.
Frequently Asked Questions
Can I replace a hardwired alarm with a battery smart detector?
That depends on the existing alarm circuit, local requirements, and the replacement instructions for both devices. A battery alarm may not preserve the interconnection or backup behavior of a hardwired system. Check whether the home relies on linked alarms and whether its wiring must remain in use. If you are unsure, have a qualified installer review the setup before removing a wired alarm. Choose a model that provides the required coverage and communication for that location.
Will a Ring-compatible Kidde alarm work without a Ring system?
Check the exact model’s setup guide to see which functions work independently and which depend on Ring equipment or services. A product name that mentions Ring does not by itself explain every connectivity requirement. If you already use Ring, confirm that the alarm appears among supported devices and that household members can receive the alerts they need. If you do not use Ring, compare the standalone alarm behavior and app requirements with other options in this roundup. That check can prevent buying a device whose connected features do not fit your home.
Should I choose an interconnected six-pack or several independent smart alarms?
Choose based on how the alarms communicate and how you want people in different rooms to be warned. Interconnected devices can make a local alarm in one area audible elsewhere, while independent smart alarms may send separate phone notifications without linking their sirens. Confirm that all units in a pack are compatible with one another and suitable for your installation type. For a larger home, map locations first and check whether the system can cover each floor as intended. A phone alert alone should not be assumed to replace audible warning throughout the home.
Do combined smoke and CO alarms replace every separate alarm in a home?
Not necessarily. The number and placement of alarms depend on the home’s layout, applicable safety rules, and the device’s instructions. A combined detector covers two hazards at its location, but it does not automatically provide the coverage of alarms placed elsewhere. Review your existing alarm map and identify whether any rooms or floors still need dedicated devices. Follow local code and the manufacturer’s placement guidance when deciding what to replace or add.
What should I check before installing a smart alarm in a rental?
First identify whether the current alarm is hardwired, connected to other alarms, or maintained by the landlord. Ask before changing wiring, removing a supplied alarm, or adding a device that could affect the building’s system. Check whether the new alarm can be installed without permanent changes and whether its app setup requires the tenant’s own network. Keep the required local alarms in place and follow the property’s safety procedures. A smart add-on should supplement an approved setup only when the building rules allow it.
Conclusion
For most buyers seeking a connected combined alarm and already-compatible wiring, I recommend the First Alert SC5 Hardwired Smart Smoke and Carbon Monoxide Alarm as the best overall fit. The X-Sense SC06-W 6-Pack is my value-minded choice for buyers planning interconnected coverage across several locations, while the First Alert SC5 Battery model is a practical pick for homes without suitable hardwiring. Beginners who already use Ring may find the Kidde Ring models easier to fit into a familiar setup; those who do not use Ring should compare their connectivity requirements first. For dedicated CO monitoring, consider the Kidde CO model or HEIMAN gateway pack based on the monitoring and setup features you need. Match the final choice to your wiring, hazard coverage, and alert ecosystem, then confirm model compatibility and local placement rules.
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