10 Best Smart Smoke Detectors

Smart smoke detectors: what matters

The strongest starting point is verification of the exact product model, not just the manufacturer or product family. Look for a current third-party U.S. listing to UL 217 for residential smoke alarms and, when carbon monoxide is claimed, UL 2034 for residential CO alarms. A registry entry should match the model number and the physical product label. Relevant records include UL Solutions Product iQ and Intertek's ETL Listed Product Directory; an OSHA Nationally Recognized Testing Laboratory listing explains why the testing organization is recognized, but is not by itself proof that a particular alarm is listed. The installation manual and back label should agree with the online listing.

UL 217 edition and test scope also matter. Newer requirements include more demanding fire scenarios and cooking-nuisance testing. That does not mean an alarm will never sound during cooking, and certification is not the same as an independent, product-specific ranking of fire response or nuisance resistance. Buyers should still follow the placement instructions, especially around cooking appliances, bathrooms, garages, fuel-burning equipment, and high-airflow locations.

Separate the alarm's core function from its headline smart features. A claim such as “smart,” “app enabled,” “real-time alerts,” or “interconnected” may mean phone notifications, local radio linking, wired alarm-to-alarm signaling, or merely compatibility with a gateway. Check whether linked alarms still sound without Wi-Fi, internet, cloud service, a hub, or a phone. App notifications should be treated as supplemental. Also check whether a carbon monoxide-only product is being presented near smoke alarms in a way that could imply broader protection, and whether a smoke-only product is being mistaken for a combination alarm.

Numbers can mislead when their conditions are omitted. An 85 dB rating is normally tied to a stated distance, such as 10 feet or 3 meters, and does not guarantee that every occupant will hear it through walls or while asleep. “Ten-year battery” may refer to expected battery life, sensor life, or the complete alarm's service life; some supplied products use replaceable batteries while others require replacing the entire sealed alarm. A displayed CO reading, indoor-air-quality feature, or low-level alert is not automatically a certified life-safety function. A product's internal comparison or manufacturer claim is not an independent test result.

Recurring cautions in the supplied reviews are important. Several products are not hardwired and cannot activate every alarm in the home; others require compatible wiring or a particular interconnect family. Several have conflicting app, Wi-Fi, interconnection, battery-life, or UL-edition claims. Exact current listing confirmation was unavailable for multiple products, and physical labels or production dates may matter when older and newer standards coexist. Sealed lithium alarms become electronic and battery waste at end of life, while replaceable batteries require ongoing maintenance. No supplied product should be treated as a substitute for following local requirements, the installation manual, regular testing, timely battery replacement, or a separate alarm when its stated scope does not cover the hazard.

Integrity

Full reviews

#1 - Best Overall

Wireless Smoke and CO Detector 6-Pack

Buyer Score 99/100Integrity Score 82/100X-Sense

Overview

This is a six-unit set of battery-powered, ceiling or wall-mounted combination smoke and carbon monoxide alarms. Each unit uses a photoelectric smoke sensor and electrochemical carbon monoxide sensor, plus an LCD, test and silence button, and radio link intended to make connected alarms sound together. It is designed for ordinary indoor family living spaces, not kitchens, garages, bathrooms, or commercial or industrial installations. The key evidence is strong for the claimed smoke and carbon monoxide functions. Intertek's current listed-product directory specifically names this product among battery-operated photoelectric smoke and carbon monoxide alarms evaluated to UL 2034. Independent product-label imagery also shows an ETL mark and claims certification to UL 217 ninth edition and UL 2034 fifth edition. The manufacturer states that two nonreplaceable CR123A lithium batteries provide a 10-year life, that up to 18 compatible units can link, and that the local alarm is at least 85 dB at 10 feet. Its product page confusingly advertises a smart app, while its own FAQ says this radio-only version is not Wi-Fi compatible and cannot use an app.

What works

• The exact product is named in Intertek's listed-product directory for residential carbon monoxide detection to UL 2034.
• Independent product-label imagery identifies ETL listing and certification claims to UL 217 ninth edition and UL 2034 fifth edition.
• Each unit has a local audible alarm, visual indicator, smoke and CO alarm patterns, and an LCD CO display, as documented in the manual.
• Radio interconnection does not depend on home Wi-Fi, cloud service, or phone access, according to the manufacturer.

What does not

• The manufacturer's own product page lists a smart app, but its FAQ says this version cannot use an app, Wi-Fi, Alexa, or other assistants. That is a direct claim-scope contradiction.
• No product-specific independent fire-response or cooking-nuisance performance report was located. The certification evidence is strong, but it is not the same as published testing of this exact unit in a kitchen.
• The sealed lithium batteries cannot be replaced. A low-battery, fault, or end-of-life signal requires replacing the complete alarm.
• The manual excludes kitchens, garages, bathrooms, furnace rooms, and commercial or industrial settings, so placement planning is essential.

Who is it for

This set suits an owner of a multi-room or multi-story home who needs several battery-operated combination alarms to sound together without running interconnect wiring. It fits retrofit situations where access to wiring is difficult and where a phone alert is not a required part of the warning plan. The six-unit format is practical for covering sleeping areas, hallways, and living spaces when locations are selected according to the manual and applicable local requirements. The 10-year sealed battery is useful where routine battery changes are likely to be missed.

Who is it not for

It is not suited to buyers who need phone notifications, Alexa control, professional monitoring, or cloud-connected status information. Despite a confusing app claim on the product page, the manufacturer says this version is not Wi-Fi compatible. It is also not for commercial or industrial installations, or for mounting in garages, kitchens, bathrooms, furnace rooms, or locations outside its temperature and humidity limits. Households that need hardwired alarms, specific voice and location messaging, or compatibility with a particular existing interconnect system should confirm those requirements separately.

Integrity

The central health finding is that the exact product appears in Intertek's directory as a battery-operated photoelectric smoke and carbon monoxide alarm evaluated to UL 2034. Product-label imagery separately shows an ETL mark and smoke certification claim to UL 217 ninth edition. That matters because the newer UL 217 requirements include tougher polyurethane fire scenarios and a cooking-nuisance test. Certification does not eliminate cooking alarms, and NIST research found current-generation alarms still varied in nuisance resistance across cooking scenarios. The unit uses photoelectric smoke sensing rather than an ionization source, and an electrochemical sensor for carbon monoxide. Its two sealed lithium metal batteries are manufacturer-stated to last 10 years, which can reduce routine battery replacement and premature disposal. The tradeoff is that the entire alarm must be replaced at battery end of life. The manual gives disposal instructions but does not provide detailed U.S. recycling guidance for the integrated batteries. EPA guidance says lithium primary batteries and electronics should be kept out of household recycling and managed through appropriate battery or electronics collection options.

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#2 - Hot Deal

Wireless Smoke and CO Detector, SC06-W

Buyer Score 96/100Integrity Score 78/100X-Sense

Overview

This product is a six-unit, battery-powered residential smoke and carbon monoxide alarm set. Each round alarm combines a photoelectric smoke sensor, an electrochemical carbon monoxide sensor, a sealed lithium battery, a test and hush button, and local audible and visual alerts. Units are installed on a wall or ceiling and communicate directly by radio, rather than requiring household Wi-Fi or a hub for primary interconnection. Intertek’s public directory independently lists the exact product family for UL 2034 carbon monoxide detection. X-Sense states that the smoke function is ETL certified to UL 217 and that the device uses a 10-year sealed battery. Its current product page says a network supports up to 18 units, while the installation manual attached to the marketplace listing says 24. That discrepancy, plus an unclear “smart app” claim, makes it important to follow the included manual and the unit’s back label.

What works

• Intertek independently lists the exact product family for UL 2034 carbon monoxide protection.
• Direct radio interconnection keeps the primary whole-home alarm function independent of Wi-Fi, cloud service, and a phone.
• The manufacturer specifies a photoelectric smoke sensor and electrochemical CO sensor, with distinct smoke and CO alarm patterns.
• The stated 10-year sealed lithium power supply avoids annual battery replacement under its specified operating conditions.

What does not

• Public verification located for this exact product family confirms UL 2034 CO listing, but a current public Intertek smoke-listing record for the exact wireless version was not located in this review.
• The manufacturer’s current page says up to 18 interconnected units, while the marketplace manual says 24. Network planning should use the documentation supplied with the units.
• This is not a hardwired alarm, so it is not a direct replacement where local code, an inspector, or an existing system requires AC-powered interconnected alarms.
• The sealed battery cannot be replaced. The entire alarm must be replaced at its stated 10-year service end, creating electronic and lithium-battery waste.

Who is it for

This set suits a homeowner or landlord who needs several battery-operated combination alarms across a small or medium residence and cannot readily add interconnect wiring. It is particularly relevant where whole-home audible warning is wanted without depending on Wi-Fi, a subscription, or phone access. The radio network can extend an alarm signal from the initiating unit to compatible units elsewhere in the home. Installation still needs to follow the placement diagram and local requirements, especially around sleeping areas, fuel-burning equipment, and kitchens.

Who is it not for

It is not suited to homes that must retain or install hardwired alarms under local building rules, insurance requirements, or an electrician’s plan. It also is not ideal for buyers who require verified voice evacuation instructions, room-specific spoken messages, or independently documented app-security support. Households with frequent cooking-smoke alarms should be especially careful about placement. Modern UL 217 tests address a cooking nuisance scenario, but NIST research shows that even newer alarms can still sound during real cooking activities.

Integrity

The most important health finding is the independently confirmed UL 2034 carbon monoxide listing for the exact product family. The manufacturer also documents photoelectric smoke sensing, electrochemical CO sensing, at least 85 dB local sound at 10 feet, separate alarm patterns, fault indication, and a 10-year replacement point. The primary radio interconnection is a practical resilience feature because local and linked alarms do not depend on household internet service. No CPSC recall or safety warning specific to this product was located in the review. However, the documentation is not fully consistent about its interconnection limit and smart-app scope. Environmentally, the sealed lithium battery can reduce routine disposable battery use over the stated service life, but it also means each unit becomes electronics waste at replacement. The reviewed materials did not provide product-specific U.S. recycling instructions for the alarm and embedded batteries.

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#3

X-Sense Smoke and Carbon Monoxide Detector Combo

Buyer Score 93/100Integrity Score 82/100X-Sense

Overview

This three-unit set is a ceiling or wall mounted, battery-only combination alarm for residential smoke and carbon monoxide detection. Each round unit measures about 5.7 inches across and uses a photoelectric smoke sensor, an electrochemical CO sensor, a test and silence button, status LEDs, and an LCD that displays CO readings and battery status. It is designed to operate as a standalone local alarm, not as a hardwired household system. The most important verification is that Intertek's current ETL directory names SC01 among battery-operated photoelectric smoke and CO alarms listed to UL 2034. X-Sense also states that the current SC01 meets UL 217 9th Edition, has a sealed lithium battery for about 10 years, and sounds at least 85 dB at 3 m. However, the product record does not provide a back-label or manufacture date, which matters because X-Sense says earlier U.S. units were made to the older UL 217 6th Edition standard.

What works

• Intertek's ETL directory specifically names SC01 in its listing for residential carbon monoxide alarms to UL 2034.
• The product combines photoelectric smoke sensing and electrochemical CO sensing in each unit, rather than treating CO as an app-only feature.
• A local audible alarm rated at least 85 dB at 3 m and visible indicators work without a phone, Wi-Fi, cloud service, or hub.
• X-Sense states that the sealed lithium battery, automatic self-checking, low-battery warning, fault indication, and end-of-life warning are built in.

What does not

• This standalone model does not provide automatic whole-home alarm activation, hardwired backup, room-specific voice messages, or confirmed app alerts.
• The current product page groups Smart App and Interconnected Alarm language beside this standalone model, creating avoidable ambiguity about functions this unit itself does not appear to provide.
• The current model is listed, but the supplied product record lacks a photo of the ETL back-label or production date. That prevents confirmation that a delivered unit is from the current UL 217 9th Edition production.
• A sealed 10-year battery prevents routine replacement, but it also means the complete alarm becomes electronic and lithium-battery waste at end of life. Clear U.S. recycling instructions were not located.

Who is it for

This set suits a homeowner or renter who needs three independent combination smoke and CO alarms in locations where hardwiring is impractical, such as bedrooms, hallways, or a finished basement. It is most appropriate for buyers who value a sealed long-life battery, a local LCD CO indication, and straightforward screw mounting, and who can place each alarm according to the installation instructions. It also fits households that do not need every alarm to activate together or send remote notifications.

Who is it not for

It is not suited to homes that require a code-specified hardwired and interconnected alarm system, or where occupants need one activated alarm to notify the entire house. It is also a poor fit for buyers seeking verified phone alerts, professional monitoring, voice evacuation instructions, or an app-managed safety system. Buyers receiving older stock should not rely on a web listing alone, because the model's current standard status should be confirmed from the physical ETL label and manufacture information.

Integrity

The core health evidence is stronger than a self-declared standards claim. Intertek's ETL directory identifies SC01 as a listed battery-operated photoelectric smoke and carbon monoxide alarm evaluated to UL 2034. X-Sense identifies current SC01 production as meeting UL 217 9th Edition. That newer smoke-alarm standard addresses more demanding fire scenarios and includes a cooking-nuisance test, though NIST research shows compliant modern alarms can still nuisance-alarm during some cooking activities. Correct placement remains important. X-Sense publicly acknowledges that certain earlier U.S. units were produced to UL 217 6th Edition and offers an upgrade or refund program for qualifying purchases from June 30, 2024 through December 31, 2025. No product-specific CPSC recall was located in the searched public recall sources. The sealed battery can reduce disposable battery use over its stated life, but the whole alarm needs responsible electronics and lithium-battery recycling when its end-of-life signal occurs.

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#4

Wireless Smoke and CO Detector XP0H-WN

Buyer Score 88/100Integrity Score 78/100X-Sense

Overview

This three-pack contains battery-powered combination smoke and carbon monoxide alarms for ceiling or wall mounting in a home. Each unit uses a photoelectric smoke sensor and electrochemical carbon monoxide sensor, according to the product documentation. It uses radio-frequency interconnection rather than hardwiring, so a detection event is intended to trigger compatible linked alarms throughout the home. The claimed network limit is 24 compatible units. The most important independently confirmed point is carbon monoxide protection. Intertek's current listed-products record specifically names this product model and says the listed devices were evaluated to UL 2034. X-Sense separately states that this model is certified to UL 217, 9th Edition for smoke alarms, which includes newer fire and cooking-nuisance test requirements, but an equivalent public Intertek smoke-listing record was not located. The sealed lithium battery and 10-year service-life claim are manufacturer-stated.

What works

• Intertek independently lists the exact product model for residential carbon monoxide detection to UL 2034.
• X-Sense identifies this model as meeting UL 217, 9th Edition, whose modern smoke-alarm requirements include polyurethane-fire and cooking-nuisance testing.
• Radio interconnection is designed to make compatible alarms sound together without depending on Wi-Fi, cloud service, or a phone.
• The manufacturer states that the sealed lithium battery powers the alarm for its 10-year intended service life.
• A U.S. support channel, five-year quality warranty, and lifetime technical support are stated by the manufacturer.

What does not

• Public third-party verification located for this exact model covers UL 2034 carbon monoxide protection, but not a separate public registry entry for its claimed UL 217 smoke listing.
• No product-specific independent performance testing was found beyond the certification evidence. A current UL 217 listing supports baseline testing, not superior real-world cooking-nuisance performance.
• The radio connection is useful for local alarm propagation, but the available evidence does not establish a detailed outage, interference, pairing-loss, or radio-security policy for this exact model.
• The sealed battery cannot be replaced. At end of life, the entire alarm becomes electronic waste containing a lithium-metal battery.
• No model-specific recycling or take-back instructions were located in the reviewed product materials.

Who is it for

This product suits a household that needs several battery-powered combination smoke and carbon monoxide alarms in locations where adding interconnect wiring would be disruptive or impractical. It is particularly relevant for owners who want a local whole-home warning system, rather than depending on Wi-Fi notifications, and who prefer not to schedule routine battery replacement. Installation still needs to follow local placement rules, especially around bedrooms, levels of the home, fuel-burning equipment, and cooking areas. Buyers should retain installation and replacement-date records for all three units.

Who is it not for

It is not suited to a buyer who needs hardwired alarms with electrical backup because these units are not hardwired. It is also a poor fit where a local authority, landlord, insurer, or renovation permit requires a specific wiring arrangement or a particular listed interconnect ecosystem. Households seeking app notifications, professional monitoring, detailed cybersecurity commitments, or documented smart-home integrations should not infer those functions from this radio-interconnected product. Anyone installing near cooking equipment should follow placement guidance rather than relying on certification alone to prevent nuisance alarms.

Integrity

The strongest health evidence is the independently traceable Intertek listing for the exact product model under UL 2034, the U.S. residential carbon monoxide alarm standard. Intertek is an OSHA-recognized Nationally Recognized Testing Laboratory. X-Sense also names this model among its UL 217, 9th Edition smoke-alarm products. That edition includes more demanding modern fire scenarios and a cooking-nuisance test, although the public smoke-listing record for this exact model was not located. The product combines photoelectric smoke sensing with electrochemical carbon monoxide sensing, according to its documentation. Its radio interconnection is a safety-positive design because local interconnected warning does not require internet service. The sealed 10-year lithium battery reduces routine disposable battery use, but it also means replacing and recycling the entire alarm at end of life. Lithium-metal batteries and devices containing them should not go in curbside recycling or household trash when a suitable battery or electronics recycler is available.

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#5

Heiman Smoke and Carbon Monoxide Detector 3-Pack

Buyer Score 86/100Integrity Score 72/100HEIMAN

Overview

This is a three-pack of round, battery-only combination alarms for residential smoke and carbon monoxide warning. Each unit is listed as 4.91 inches across and 1.46 inches deep, with a photoelectric smoke sensor, electrochemical carbon monoxide sensor, test or silence control, LED indication, mounting hardware, and a sealed 10-year battery. The product is a standalone alarm, not a Wi-Fi, app, or whole-home interconnection system. Retailer descriptions state an 85 dB audible alarm, visual LED warning, alarm-memory indication, and end-of-life notification. Listings also claim conformity with current smoke and carbon monoxide standards, but an exact-model record could not be confirmed in the public UL or Intertek registry results reviewed. That leaves the central life-safety listing claim insufficiently independently documented for this specific product.

What works

• Three self-contained alarms can cover separate rooms without wiring, based on the documented standalone battery format.
• The sealed 10-year battery is a manufacturer-stated maintenance benefit that avoids routine battery replacement.
• Manufacturer-distributed descriptions specify separate photoelectric smoke and electrochemical carbon monoxide sensors.
• Retailer descriptions state an 85 dB local siren with flashing LED indication and a test or silence control.

What does not

• The exact product's claimed U.S. life-safety certification could not be matched to a public UL or Intertek listing record during review.
• Claims are inconsistent across product descriptions, including references to UL certification, ETL listing, and differing carbon monoxide standard editions.
• This is a standalone unit, so one alarm is not documented to activate alarms elsewhere in the home.
• No exact installation manual or back-label was located to independently verify alarm tones, replacement timing, placement limits, or all fault indications.

Who is it for

This format suits a household that needs several self-contained combination alarms in existing rooms where running interconnect wiring is impractical. It is most relevant where a local smoke and carbon monoxide alarm, a compact ceiling or wall installation, and a manufacturer-stated 10-year sealed power source are the required functions. Users should be prepared to test each unit regularly, document its installation date, follow local placement requirements, and retain packaging or labels that show the applicable safety mark.

Who is it not for

It is not suited to buyers who need documented hardwired or wireless whole-home alarm activation, app notifications, location-specific voice messages, or a public certification-registry match before installation. It is also not the right format for a new-build or renovation project when local code, an inspector, or a landlord requires a specifically listed and interconnected alarm system. Households needing verified accommodation features, such as bed-shaker or high-intensity visual notification support, need equipment expressly documented for those needs.

Integrity

The product combines smoke and carbon monoxide functions in one battery-powered enclosure. Its stated sensor configuration is photoelectric for smoke and electrochemical for carbon monoxide, which is a technically appropriate pairing for the two claimed hazards. Product descriptions also state an 85 dB local alarm, flashing LED, test control, end-of-life warning, and sealed 10-year lithium battery. Those are manufacturer or retailer statements, not findings independently confirmed from an exact-model public certification entry or manual. No product-specific CPSC recall or safety warning was located in the sources reviewed. The housing is listed as ABS plus PC plastic. A long-life sealed battery can reduce routine disposable-battery changes, but it makes the expired alarm an electronics and battery waste item. EPA guidance says lithium batteries and devices containing them should not go in household trash or curbside recycling. Use a battery or electronics collection option that accepts the complete device, and follow local handling instructions.

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#6

First Alert Interconnect Smoke & CO Alarm

Buyer Score 85/100Integrity Score 80/100First Alert

Overview

This is a round, hardwired residential combination alarm for smoke and carbon monoxide, designed for a 120V ceiling or wall junction box. It uses an ionization smoke sensor and an electrochemical carbon monoxide sensor, and it needs one replaceable 9V alkaline battery for backup power. The manual limits its intended use to single-family residences, not marine or RV settings. The product's back-label text in the manufacturer manual states that it conforms to UL 217 and UL 2034, and the manufacturer identifies it as meeting UL 217 eighth-edition requirements. A current public UL Product iQ registry match for this exact product was not independently located during this review. It provides a minimum 85 dB local horn at 10 feet, separate smoke and CO horn patterns, wired interconnection, fault alerts, and an end-of-life signal at about 10 years.

What works

• Hardwired primary power with a replaceable 9V backup can preserve local alarm operation during an outage.
• The manual specifies a minimum 85 dB alarm at 10 feet, with three-beep smoke and four-beep CO alarm patterns.
• Its wired Smart Interconnect function triggers compatible alarms without relying on Wi-Fi, cloud service, or phone access.
• The manual gives distinct low-battery, malfunction, and end-of-life signals, and directs replacement 10 years after installation.
• The smoke and CO functions are described separately, with an ionization smoke sensor and electrochemical CO sensor.

What does not

• The manufacturer states UL 217 and UL 2034 conformance, but this review did not independently confirm a current exact-product listing in UL's public certification registry.
• This uses an ionization-only smoke sensor. NIST research finds ionization alarms can be more prone to cooking nuisance alarms, so placement away from cooking sources is particularly important.
• The product is not a Wi-Fi smart detector. Its Smart Interconnect name refers to wired alarm-to-alarm signaling, not app alerts or remote notifications.
• Not every older interconnected alarm will relay a CO event. The manual says units lacking Smart Interconnect remain silent during a CO alarm.
• The backup battery is a disposable 9V alkaline cell, and the manual does not provide product-specific battery or electronics recycling instructions.

Who is it for

This product fits an owner or qualified installer replacing a compatible 120V hardwired alarm in a single-family home, especially where existing interconnect wiring is already present. It suits households that want combined smoke and CO detection, loud local warnings, and whole-home wired alarm signaling that remains independent of internet access. It is also appropriate for someone prepared to test the unit, maintain the 9V backup battery, confirm interconnect compatibility, and replace the alarm at its stated 10-year end of life.

Who is it not for

It does not suit renters or homeowners without an existing compatible hardwired junction-box installation unless a qualified installer will add wiring. It is not intended for RVs, boats, garages, unfinished attics, or very hot, cold, humid, insect-prone, or kitchen-adjacent locations identified in the manual. Households wanting phone notifications, remote status, or app-based silence controls need a genuinely connected alarm system. It is also a poor fit where users cannot reliably replace a 9V backup battery or test the interconnected network.

Integrity

The key health protection is combined local detection of smoke and carbon monoxide. The manufacturer manual identifies an ionization smoke sensor and electrochemical CO sensor, specifies distinct audible patterns for smoke and CO, and states a minimum 85 dB output at 10 feet. Its back-label text states conformance to UL 217 and UL 2034, although an exact current listing record in the public UL registry was not independently confirmed here. No current CPSC recall specific to this product was identified in the review search. The hardwired design avoids relying on batteries as the only primary power source, but it still uses a replaceable disposable 9V alkaline backup battery. The manual calls for replacement of the entire alarm 10 years after installation and provides an end-of-life alert. That defined replacement date can prevent long-term use of an expired sensor, but creates electronics waste. Follow local e-waste and battery-recycling rules rather than putting the alarm or its battery in household recycling.

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#7

Heiman 3-Pack Smart CO Detectors with Gateway

Buyer Score 82/100Integrity Score 74/100HEIMAN

Overview

This product is a three-unit residential carbon monoxide alarm set with a gateway. Each C1-R is a round, battery-powered alarm intended for wall or ceiling mounting. HEIMAN specifies a 3 V CR123A lithium battery, a proprietary 915 MHz radio link, local audible and visual warning, and a claimed sound level of at least 85 dB at 10 feet. The manufacturer also identifies an electrochemical CO sensor and a 10-year service claim. This is not a smoke alarm, heat alarm, natural-gas detector, or general air-quality monitor. The product manual expressly limits detection to carbon monoxide at the sensor. HEIMAN states that the model is ETL Listed to UL 2034, and a manufacturer manual says it conforms to UL 2034 and CSA 6.19-17. FCC authorization evidence supports the presence of the 915 MHz radio, but it does not independently establish the product's life-safety listing. An issuing-body directory match for the exact model was not located during this review.

What works

• The product has a clear CO-only scope, which reduces the risk of mistaking it for a smoke or combustible-gas alarm.
• The manual documents a local audible alarm, flashing indication, test button, hush function, low-battery signal, malfunction signal, and end-of-life signal.
• HEIMAN states that linked C1-R alarms use local 915 MHz radio communication, so primary alarm propagation is designed not to depend on household Wi-Fi.
• The manufacturer states that the system can provide room-specific information through a compatible gateway or app.

What does not

• It cannot replace smoke alarms, heat alarms, or combustible-gas detectors. Its manual specifically says it does not detect smoke, fire, or other gases.
• The claimed ETL listing to UL 2034 is plausible and appears in HEIMAN materials, but this review did not locate a current issuing-body directory record matching the exact model and label.
• The product's smart functions introduce account and household-data handling. HEIMAN's privacy policy describes collection of device identifiers, Wi-Fi information, location-related data, logs, and room settings for some functions.
• Public documentation provides limited detail on a defined security-update period, end-of-support commitment, vulnerability disclosure process, or electronics and lithium-battery recycling instructions.

Who is it for

This product suits a household that needs interconnected carbon monoxide coverage in a home with fuel-burning appliances, a fireplace, generator exposure, or an attached garage, and that already understands it must maintain separate smoke alarms. It is especially relevant where running interconnect wiring is impractical, because HEIMAN states the C1-R units communicate by local 915 MHz radio. Buyers should be comfortable following placement, weekly testing, battery, and end-of-life instructions, and should treat the app and gateway as supplemental notification rather than their sole warning path.

Who is it not for

It is not for anyone seeking a single device to address smoke, fire, CO, natural gas, propane, or indoor-air-quality hazards. The manual limits this product to carbon monoxide detection. It is also unsuitable as a substitute for code-required hardwired alarms where a local authority requires that arrangement. Households needing independently documented confirmation of the exact current U.S. life-safety certification should seek that confirmation from the physical product label and the issuing laboratory before relying on installation. People unwilling to use connected-app data practices should avoid enabling the smart functions.

Integrity

The key health point is scope. This product is intended to warn of carbon monoxide, a colorless toxic combustion gas, through a local horn and visual indication. HEIMAN specifies an electrochemical sensor, a local alarm of at least 85 dB at 10 feet, and RF-linked alarms. The manual gives emergency instructions, requires regular testing, and says the alarm does not detect smoke, fire, or other gases. A separate smoke alarm remains necessary. HEIMAN claims ETL certification to UL 2034 for this model, but an exact current directory match from the issuing laboratory was not found in this review. No product-specific CPSC recall or safety warning was located. The C1-R uses a lithium CR123A battery and is an electronic device, so it should not enter household trash where local battery or e-waste rules prohibit it. HEIMAN's public materials did not provide clear product-specific recycling guidance or a published long-term security-support commitment.

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#8

Heiman Smart Wireless Smoke Detector Set

Buyer Score 81/100Integrity Score 72/100HEIMAN

Overview

This set combines six battery-powered S1-R photoelectric smoke alarms with a smart gateway. The alarms are small ceiling or wall units, about 2.76 inches across, designed to sound locally and relay an alarm to the other S1-R units through a 915 MHz radio network. The gateway is intended to add app-based notifications and smart-home functions. The strongest independently confirmed fact is that Intertek's public directory lists the exact S1-R model as ETL Listed to UL 217, Edition 9. HEIMAN states that the model provides at least 85 dB at 10 feet and direct radio interconnection that does not depend on household Wi-Fi. However, the product materials conflict on battery duration and UL edition, so the advertised 10-year battery and UL 217 10th Edition wording should not be treated as confirmed for this product.

What works

• The exact S1-R model appears in Intertek's public directory as ETL Listed to UL 217, Edition 9.
• HEIMAN states that S1-R units use direct 915 MHz radio interconnection, so the primary alarm-to-alarm link is not dependent on Wi-Fi or the gateway.
• HEIMAN specifies a local sound level of at least 85 dB at 10 feet, which supports an independently useful in-home warning.
• The product is smoke-only, with no unsupported carbon monoxide or heat-detection function implied by the verified listing.

What does not

• The listing's UL 217 10th Edition claim conflicts with Intertek's exact-model record, which identifies UL 217 Edition 9.
• Battery claims are inconsistent. The catalog says 10 years, while HEIMAN's current S1-R specification lists 8.3 years and a 10-year sensor lifespan.
• The bundled gateway's exact certification, outage behavior, and role in app alerts were not independently documented. Phone notifications should be treated as supplemental.
• The companion app's App Store privacy disclosure says location may be used for tracking and that account, contact, and other data may be linked to identity. No product-specific security update or end-of-support commitment was found.

Who is it for

This product suits an owner of an existing home who needs to add interconnected smoke alarms without running interconnect wiring, and who can install and test six units according to local placement rules. It is most appropriate where direct local alarming matters more than app convenience, because HEIMAN describes the S1-R radio link as independent of Wi-Fi. It also suits a buyer who can keep a written replacement schedule rather than relying on the inconsistent battery-life wording.

Who is it not for

It is not suited to anyone who specifically requires documentation for UL 217 10th Edition, a hardwired system with building-power backup, or a combination smoke and carbon monoxide alarm. It is also a poor fit for privacy-sensitive households that do not want location and account-linked data associated with a safety app. New construction, rental properties, multifamily buildings, and homes subject to local inspection requirements should confirm the required alarm type, interconnection method, and placement with the authority having jurisdiction.

Integrity

The core life-safety evidence is meaningful but narrower than the sales wording suggests. Intertek lists the exact S1-R smoke-alarm model as ETL Listed to UL 217, Edition 9. UL 217 Edition 9 includes more demanding modern fire and cooking-nuisance testing than older editions. HEIMAN identifies the sensing method as photoelectric and specifies at least 85 dB local sound at 10 feet. The product is not a carbon monoxide alarm. The main concern is documentation consistency. HEIMAN currently lists 8.3 years of battery life for S1-R, while the product listing says 10 years, even though HEIMAN separately states a 10-year sensor lifespan. The sealed lithium battery and electronics will ultimately require responsible e-waste handling. No product-specific recycling instructions were located. No HEIMAN S1-R recall or CPSC safety warning was located in the reviewed public sources, but the app privacy disclosure indicates potentially broad data handling for users who activate connected features.

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#9

Combination Smoke and CO Detector

Buyer Score 79/100Integrity Score 77/100X-Sense

Overview

The X-Sense SC07 is a round, battery-operated combination smoke and carbon monoxide alarm for indoor ceiling or wall installation. It uses a photoelectric smoke sensor and an electrochemical carbon monoxide sensor, with a front LCD intended to show CO readings and status. X-Sense states that it has a nonreplaceable 10-year lithium battery, an 85 dB or greater local alarm at 3 m, and a test and silence button. The current Intertek directory independently identifies the exact SC07 model as a battery-operated photoelectric smoke and CO alarm listed to UL 2034 for carbon monoxide detection. X-Sense also states that it is ETL certified to UL 217 for smoke detection, but the independently accessible Intertek record located for this review specifically documents the CO standard. This is a standalone alarm, not a Wi-Fi product and not an interconnected whole-home system.

What works

• The exact SC07 model appears in Intertek's ETL directory for UL 2034 carbon monoxide alarm compliance.
• It combines smoke and CO sensing in one locally audible unit, using photoelectric and electrochemical sensors, according to X-Sense.
• The manufacturer specifies a sealed lithium battery and approximately 10 years of operating life, avoiding routine battery changes.
• It does not rely on Wi-Fi, an app, cloud service, or phone access for its primary local alarm.

What does not

• It is a standalone alarm, so an alarm in one room does not trigger units elsewhere in the home.
• The independently accessible listing located for this review verifies UL 2034 CO coverage. X-Sense states UL 217 smoke compliance, but a matching public smoke-listing record was not located.
• The product page is internally inconsistent, showing Smart App and Interconnected Alarm among its function labels while its own FAQ says this unit is not Wi-Fi compatible, app controlled, or interconnected.
• Public product information reviewed does not provide clear, model-specific recycling instructions for the sealed lithium battery and electronic alarm at end of life.

Who is it for

This product suits someone replacing a single expired smoke and CO alarm in a heated indoor area, where a local alarm is appropriate and existing wiring is unavailable. It is particularly relevant for users who want combined CO coverage, a front display for CO readings above the stated display threshold, and no recurring battery replacement. It also fits a household that prefers a primary warning system with no app account, Wi-Fi connection, or cloud dependency. Installation still needs to follow local code and the placement instructions.

Who is it not for

It is not suited to a multi-story home or a household that needs all alarms to sound together when one unit detects danger. This model is standalone, so it cannot supply interconnected warning across sleeping areas or floors. It is also not the right choice for buyers specifically seeking app notifications, remote status checks, smart-home control, or voice location messages. Do not use it in unheated garages, damp locations, or other settings outside the stated 40 to 100 F operating range. People especially sensitive to low-level CO exposure should note that X-Sense says the display begins above 30 ppm.

Integrity

For life safety, the strongest independent finding is the current Intertek ETL directory entry for the exact SC07, which identifies it as a battery-operated combination alarm evaluated to UL 2034 for carbon monoxide detection. X-Sense states that the same product meets UL 217 for smoke alarms and uses photoelectric smoke sensing plus an electrochemical CO sensor. The unit provides a local 85 dB or greater alarm without internet access, but it does not provide inter-unit warning. The sealed lithium battery is manufacturer-stated to last about 10 years, which can reduce disposable battery use and maintenance over the unit's service life. It also makes the product an electronic device with an embedded lithium battery that should not be placed in ordinary household trash. Clear model-specific recycling guidance was not found in the reviewed public materials. No CPSC recall or U.S. regulatory safety action specific to this model was located in the sources reviewed.

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#10

First Alert SC5 Battery Smart Smoke & CO Alarm

Buyer Score 77/100Integrity Score 77/100First Alert

Overview

This is a battery-powered smart combination alarm for residential smoke and carbon monoxide detection. It is a 5.75-inch square unit, about 1.6 inches deep, powered by six replaceable 3 V CR123A lithium batteries. First Alert identifies the smoke sensor as photoelectric and the carbon monoxide sensor as electrochemical. It connects to Wi-Fi for app alerts and can wirelessly interconnect with listed compatible alarms. The manufacturer states that this product conforms to UL 217 and UL 2034, and its product page specifies UL 217 10th Edition. Its public manual also documents 85 dB local alarm sound at 10 feet, separate smoke and CO alarm patterns, and voice location messages. A publicly accessible UL registry match for this exact battery model was not established in this review, so the manufacturer’s conformity statements should not be read as an independently verified registry result.

What works

• The manual documents loud local smoke and CO alarm patterns, plus voice messages that can identify the hazard and assigned room location.
• Manufacturer documentation supports smoke and carbon monoxide functions with photoelectric and electrochemical sensors.
• Wireless interconnect is documented for compatible SC5 alarms and Google Nest Protect alarms, so an initiating compatible alarm can trigger others.
• The six batteries are replaceable, and the manual gives low-battery, fault, testing, cleaning, and end-of-life instructions.
• The radio-bearing model has an FCC authorization record and a Wi-Fi Alliance certificate that includes WPA3-Personal support.

What does not

• The UL conformity claim is manufacturer-stated. A current public UL Product iQ listing match and back-label match for this exact battery model were not independently confirmed.
• No independent product-specific fire response or cooking-nuisance test results were located. Precision Detection and reduced nuisance-alarm language remain manufacturer claims.
• The public documentation does not clearly explain every offline and cloud-outage behavior for wireless interconnect, app alerts, and remote controls.
• Smart operation requires accounts, Wi-Fi setup, location data, and app permissions. A product-specific public security-update commitment and end-of-support policy were not located.
• This battery version requires all six specified disposable lithium cells to be replaced together, which creates recurring battery use and replacement cost.

Who is it for

This product suits a homeowner replacing battery Nest Protect alarms who wants local smoke and CO warning plus phone notifications and documented compatibility with Google Home and compatible Nest Protect units. It is most appropriate where a battery-operated alarm is acceptable under local requirements, where occupants can maintain six specified CR123A cells, and where the home has reliable Wi-Fi for supplemental mobile alerts. It also fits users who value audible voice messages and room labeling during an emergency.

Who is it not for

It is not suited to installations that require hardwired alarms, hardwired interconnection, or a sealed 10-year battery. Buyers who cannot reliably replace six specified lithium batteries at once should avoid relying on this format. It is also a poor fit for households that do not want account-linked, Wi-Fi-connected safety equipment or need a fully documented local-only smart system. People needing independently accessible registry confirmation before installation should seek that confirmation from UL and inspect the product label before use.

Integrity

The important health feature is local operation. The manual describes distinct smoke and carbon monoxide horn patterns, an 85 dB alarm at 10 feet, voice prompts, weekly testing, and instructions to replace a unit that does not pass a test. It also states that the product conforms to UL 217 and UL 2034, but this review could not independently match the exact battery model in a publicly accessible UL registry. The smart functions should therefore remain supplemental to local alarms and routine testing. The product contains electronics, Wi-Fi radio hardware, and six replaceable CR123A lithium batteries. Its manual warns against recharging, disassembling, overheating, or burning the cells, and says not to discard the product with household waste. It directs users to authorized collection or recycling centers. Replaceable batteries can prevent disposal of a whole alarm after a battery depletion, but six disposable primary lithium cells still create recurring material use. No CPSC recall matching this exact battery model was identified in the review.

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