Smarter temperature control, built around your day. The Siterwell GS366A-MWAC Smart Thermostat brings scheduling, remote control, and smart-home integration together in one simple upgrade. Create Home, Away, Sleep, and custom schedules to keep the temperature where you want it while helping reduce unnecessary heating and cooling when no one is home. Designed for most 24V residential HVAC systems, GS366A-MWAC works with many conventional heating and cooling systems, heat pumps, gas, oil, electric, and dual-fuel systems commonly found in North American homes.  Use the Siterwell Link App to adjust temperature, system modes, fan settings, and schedules from wherever you are. At home, connect GS366A-MWAC with Amazon Alexa or Google Home for hands-free control. A 3.5-inch full-color touchscreen keeps temperature, humidity, and HVAC status easy to read, while presence wake-up brings the display to life as you approach. Built-in alerts can also help surface temperature, humidity, heating, cooling, and auxiliary-heat conditions before they are easy to miss. Set your schedule. Check in from anywhere. Let GS366A-MWAC handle the rest. FCC Part 15 compliant for residential use, backed by a 3-year limited warranty. A PIN-code lock prevents accidental setting changes. Notice: C‑wire adapter GS136A-WCAN Power Extender Kit (PEK) sold separately. Protect Your Delivery For extra protection against eligible physical loss, external damage or shortage while your order is in transit—and eligible theft after delivery within the coverage term—consider adding optional Shipsurance shipping insurance when it is offered at checkout. If you purchased this coverage and a shipping-related issue occurs, review the coverage rules and contact SureCircle first to file a claim or check claim status. Product setup, technical support, product defects and manufacturer-warranty questions remain with SITERWELL. Customer Service U.S. Customer Service Hotline: +1 800-710-7321Monday–Friday, 9:00 AM–6:00 PM (EST)

GS509A: Photoelectric smoke detection for ceiling or wall mounting The SITERWELL GS509A is a standalone photoelectric smoke alarm with a mounting bracket for ceiling or wall installation, making it a practical choice for straightforward home installation. Its replaceable-battery design keeps routine maintenance accessible, with single and multipack options for planning your alarm locations. Key features Photoelectric smoke sensing: Detects smoke using an optical sensor. Mounting bracket: Fixes to the ceiling or wall following the supplied instructions. Replaceable battery: Maintain power with the battery type specified for your unit. 10-year product life: Product service life is separate from battery life; batteries need replacement during use. Test button: Check operation as part of your regular alarm maintenance. Audible alarm: Rated at ≥85 dB(A) at 10 feet (3.05 m), as stated in the product manual. Low-battery warning: A signal reminds you when the battery needs attention. Choose your home safety setup For separate carbon monoxide detection, add the  plug-in CO alarm; each device operates independently. Prefer a smoke alarm with a built-in battery designed for 10 years? Compare the GS525A 10-year battery smoke alarm. For setup, placement and routine testing, follow the instructions supplied with your alarm. Browse our product user manuals for model-specific guidance. To weigh this sensing method against the alternative, see how photoelectric and ionization smoke alarms differ. Protect Your Delivery For extra protection against eligible physical loss, external damage or shortage while your order is in transit—and eligible theft after delivery within the coverage term—consider adding optional Shipsurance shipping insurance when it is offered at checkout. If you purchased this coverage and a shipping-related issue occurs, review the coverage rules and contact SureCircle first to file a claim or check claim status. Product setup, technical support, product defects and manufacturer-warranty questions remain with SITERWELL. Customer Service U.S. Customer Service Hotline: +1 800-710-7321Monday–Friday, 9:00 AM–6:00 PM (EST)

GS886A-3RFDT: Wireless interconnected smoke and CO detectionThe SITERWELL GS886A-3RFDT (A8612B-4R) combines smoke and carbon monoxide detection with wireless alarm interconnection. It is designed for a coordinated alarm setup using compatible units, without running interconnect wiring between alarm locations.Key features Two detection functions: Smoke and CO sensing in one alarm. Wireless interconnection: Compatible, correctly paired alarms can sound together when an alarm is triggered; up to 18 alarms in one network. Built-in lithium battery: Sealed and non-replaceable; the alarm has a 10-year product life under the specified operating conditions. Bilingual voice alerts: English and French voice options accompany audible warnings. Optical smoke sensing: Multi-criteria optical sensing supports smoke detection. Choose your home safety setupFor a hardwired installation, compare the GS886A-3WCAR hardwired smoke and CO alarm. For a separate travel CO detector with a display, explore the GS828A portable CO alarm. These are selection options; any mixed-model interconnection must be confirmed before purchase.Only pair models explicitly approved in the supplied instructions. Wireless interconnection does not by itself provide Wi-Fi, app control or compatibility with every SITERWELL alarm. For help planning a system, contact SITERWELL.Protect Your DeliveryFor extra protection against eligible physical loss, external damage or shortage while your order is in transit—and eligible theft after delivery within the coverage term—consider adding optional Shipsurance shipping insurance when it is offered at checkout. If you purchased this coverage and a shipping-related issue occurs, review the coverage rules and contact SureCircle first to file a claim or check claim status. Product setup, technical support, product defects and manufacturer-warranty questions remain with SITERWELL. Customer Service U.S. Customer Service Hotline: +1 800-710-7321Monday–Friday, 9:00 AM–6:00 PM (EST)

GS886A-3NCDT: Standalone smoke and carbon monoxide protection in one alarm The SITERWELL GS886A-3NCDT combines smoke and carbon monoxide detection with bilingual voice alerts in one standalone alarm. It operates independently and does not support wireless interconnection with other alarms. Its built-in lithium battery and dual-sensor design make it a straightforward option for households that want two-hazard protection from a single device. Key features 2-in-1 smoke and CO detection: Smoke and carbon monoxide sensing functions are combined in one alarm. Standalone operation: Each GS886A-3NCDT operates independently and is not designed to interconnect with other alarms. English and French voice alerts: Spoken warnings provide additional alarm information alongside the audible alert. Built-in lithium battery: Sealed and non-replaceable; the alarm has a 10-year product life under the specified operating conditions. Optical smoke sensing: Multi-criteria optical sensing helps detect smoke conditions. Audible warning: Alerts occupants when the unit detects an alarm condition. Need interconnected alarms instead? If alarm-to-alarm interconnection is required for your home or project, compare the GS886A-3RFDT wireless interconnected smoke & CO alarm. For a hardwired interconnected option, explore the GS886F-H02 combination alarm. Always verify the exact model number and installation requirements before ordering. Follow the instructions supplied with your alarm for installation, testing and maintenance. Protect Your Delivery For extra protection against eligible physical loss, external damage or shortage while your order is in transit—and eligible theft after delivery within the coverage term—consider adding optional Shipsurance shipping insurance when it is offered at checkout. If you purchased this coverage and a shipping-related issue occurs, review the coverage rules and contact SureCircle first to file a claim or check claim status. Product setup, technical support, product defects and manufacturer-warranty questions remain with SITERWELL. Customer Service U.S. Customer Service Hotline: +1 800-710-7321Monday–Friday, 9:00 AM–6:00 PM (EST)

GS525A: Photoelectric smoke detection with a built-in 10-year battery The SITERWELL GS525A combines a photoelectric smoke sensor with a built-in, non-replaceable lithium battery and a 10-year product life. Its standalone design suits homes looking for battery-powered smoke detection without household alarm wiring. Key features Built-in lithium battery: Sealed and non-replaceable; the alarm has a 10-year product life, subject to operating conditions and the supplied instructions. Photoelectric sensor: Uses light-based sensing to detect smoke. Low-battery and fault warnings: Help identify when the alarm needs attention. Test and silence button: Makes routine checks and the specified silence functions accessible. Flexible mounting: Screws are included for wall or ceiling installation; the adhesive option ships as either 3M tape or a magnetic pad, selected at random. Choose your home safety setup Add the GS846A plug-in carbon monoxide alarm for independent CO detection alongside your smoke alarms. For a replaceable-battery smoke alarm, compare the GS509A smoke alarm. For setup, placement and routine testing, follow the instructions supplied with your alarm. Browse our product user manuals for model-specific guidance. For a photoelectric vs ionization comparison, see our guide. Protect Your Delivery For extra protection against eligible physical loss, external damage or shortage while your order is in transit—and eligible theft after delivery within the coverage term—consider adding optional Shipsurance shipping insurance when it is offered at checkout. If you purchased this coverage and a shipping-related issue occurs, review the coverage rules and contact SureCircle first to file a claim or check claim status. Product setup, technical support, product defects and manufacturer-warranty questions remain with SITERWELL. Customer Service U.S. Customer Service Hotline: +1 800-710-7321Monday–Friday, 9:00 AM–6:00 PM (EST)

GS828A: Portable carbon monoxide detection with an LCD displayThe SITERWELL GS828A is a battery-powered carbon monoxide alarm with an LCD display and audible warning. Its freestanding or wall-mounted design offers flexible placement at home or in suitable indoor travel accommodation.Key features Electrochemical sensor: Detects carbon monoxide. LCD display: Displays real-time CO levels and readings on the built-in LCD according to the alarm's display settings. Status indicators: Color-coded lights help distinguish power, fault and alarm conditions. Replaceable AA batteries: Battery power supports use without a plug-in outlet. Flexible placement: Use freestanding or wall-mounted as permitted by the supplied instructions. Choose your home safety setupFor everyday plug-in CO monitoring at home, compare the GS846A CO alarm with battery backup. To add separate smoke detection, explore the GS525A photoelectric smoke alarm. These alarms operate independently.Select locations and operating conditions permitted by the instructions supplied with your unit, and check the replacement date on its label. This product detects CO; it does not detect smoke or combustible-gas leaks. For help choosing a model, contact SITERWELL.Protect Your DeliveryFor extra protection against eligible physical loss, external damage or shortage while your order is in transit—and eligible theft after delivery within the coverage term—consider adding optional Shipsurance shipping insurance when it is offered at checkout. If you purchased this coverage and a shipping-related issue occurs, review the coverage rules and contact SureCircle first to file a claim or check claim status. Product setup, technical support, product defects and manufacturer-warranty questions remain with SITERWELL. Customer Service U.S. Customer Service Hotline: +1 800-710-7321Monday–Friday, 9:00 AM–6:00 PM (EST)

GS886A-3WCAR: Hardwired smoke and carbon monoxide detectionThe SITERWELL GS886A-3WCAR combines smoke and CO detection in a hardwired alarm with battery backup. It is an option for households planning a compatible interconnected alarm installation with both detection functions in one device.Key features Combination detection: Smoke and carbon monoxide sensing in a single housing. AC power: Designed for a 120V AC, 60Hz supply. AA battery backup: Two AA batteries support backup operation during an AC power interruption. Two ways to interconnect: Connect approved compatible units by wiring or wirelessly, up to 18 alarms in one network. 5VA flame-retardant housing: The casing meets the 5VA flame-retardancy standard. 10-year product life: Product service life is separate from the replacement schedule for backup batteries. Choose your home safety setupCompare the GS886F-H02 hardwired combination alarm for another hardwired option. For a setup using wireless alarm interconnection, review the GS886A-3RFDT smoke and CO alarm.Confirm the supported connection method, wiring and full model compatibility before combining alarms. Shared branding or a similar model name does not establish compatibility. For a mixed-model installation, contact SITERWELL before ordering.Protect Your DeliveryFor extra protection against eligible physical loss, external damage or shortage while your order is in transit—and eligible theft after delivery within the coverage term—consider adding optional Shipsurance shipping insurance when it is offered at checkout. If you purchased this coverage and a shipping-related issue occurs, review the coverage rules and contact SureCircle first to file a claim or check claim status. Product setup, technical support, product defects and manufacturer-warranty questions remain with SITERWELL. Customer Service U.S. Customer Service Hotline: +1 800-710-7321Monday–Friday, 9:00 AM–6:00 PM (EST)

GS886F-H02: Hardwired smoke and CO protection with voice alertsThe SITERWELL GS886F-H02 combines photoelectric smoke sensing and electrochemical carbon monoxide sensing in a hardwired alarm. Battery backup and bilingual voice alerts support a home safety setup built around compatible interconnected alarms.Key features Dual sensors: Photoelectric smoke detection and electrochemical CO detection in one unit. Hardwired power: Designed for a 120V AC, 60Hz supply. Lithium battery backup: Supports alarm operation during a power interruption, subject to battery condition. Wired interconnection: Compatible alarms can sound together when installed and connected as specified; up to 18 alarms in one network. Bilingual voice alerts: English and French options provide spoken warnings. Choose your home safety setupCompare the GS886A-3WCAR hardwired smoke and CO alarm when selecting a system. For a battery-powered standalone alternative, explore the GS886-H02 smoke and CO alarm.For additional 2-in-1 options, browse all combination smoke and CO detectors.Confirm wiring, connectors and the approved model compatibility list before replacing an existing alarm. Cross-links show alternatives, not a guarantee that the models can share an interconnect circuit. Review the installation manuals before selecting your setup.Protect Your DeliveryFor extra protection against eligible physical loss, external damage or shortage while your order is in transit—and eligible theft after delivery within the coverage term—consider adding optional Shipsurance shipping insurance when it is offered at checkout. If you purchased this coverage and a shipping-related issue occurs, review the coverage rules and contact SureCircle first to file a claim or check claim status. Product setup, technical support, product defects and manufacturer-warranty questions remain with SITERWELL. Customer Service U.S. Customer Service Hotline: +1 800-710-7321Monday–Friday, 9:00 AM–6:00 PM (EST)

GS846A: Plug-in carbon monoxide detection with battery backupThe SITERWELL GS846A uses an electrochemical sensor to detect carbon monoxide and plugs into a suitable 120V household outlet. Battery backup and clear status indicators make it a practical addition to a home that already has smoke alarms.Key features Electrochemical CO sensor: Dedicated sensing for carbon monoxide. Plug-in power: Designed for 120V AC household power. Battery backup: Supports operation when AC power is interrupted, subject to battery condition. Color-coded indicators: Green indicates power, yellow indicates a fault and red indicates an alarm. Audible alarm: Provides a sound warning when an alarm condition is detected. Choose your home safety setupFor smoke detection alongside this CO alarm, choose the GS525A built-in battery smoke alarm or the GS509A smoke alarm. These products provide separate detection functions and operate independently.The GS846A detects carbon monoxide; smoke and combustible-gas detection require products designed for those hazards. Follow the supplied instructions for outlet location, backup-battery care and testing. For model guidance, contact SITERWELL.Protect Your DeliveryFor extra protection against eligible physical loss, external damage or shortage while your order is in transit—and eligible theft after delivery within the coverage term—consider adding optional Shipsurance shipping insurance when it is offered at checkout. If you purchased this coverage and a shipping-related issue occurs, review the coverage rules and contact SureCircle first to file a claim or check claim status. Product setup, technical support, product defects and manufacturer-warranty questions remain with SITERWELL. Customer Service U.S. Customer Service Hotline: +1 800-710-7321Monday–Friday, 9:00 AM–6:00 PM (EST)

GS562A: Hardwired smoke detection with 9V battery backupThe SITERWELL GS562A is a hardwired smoke alarm for homes with a suitable alarm power supply and interconnect wiring. A 9V backup battery supports operation during a power interruption, while the test and silence button keeps routine checks accessible.Key features 120V AC power: Designed for a 120V, 60Hz household supply. 9V battery backup: Maintains backup power when the battery is correctly installed and in working condition. Wired interconnection: Supports up to 12 compatible units installed according to the instructions. Test and silence button: Provides access to operational checks and the specified silence function. Single and multipack options: Choose the pack quantity for your installation plan. 10-year product life: The alarm is designed for up to ten years of service, with scheduled battery replacement. Silence for about 10 hours: Press the test button to silence low-battery or fault signals and avoid nighttime disturbance. Status indicators: In normal operation the green LED stays on and the red LED flashes periodically, such as every 40 seconds. Choose your home safety setupFor separate CO detection alongside your smoke alarm circuit, add the GS846A plug-in carbon monoxide alarm, which operates independently. If your project calls for smoke and CO sensing in a single hardwired unit, compare the GS886F-H02 combination alarm.Confirm wiring and model compatibility before installing or replacing interconnected alarms. The comparison link does not establish electrical compatibility with GS562A. Review the product installation manuals for the correct system configuration.Protect Your DeliveryFor extra protection against eligible physical loss, external damage or shortage while your order is in transit—and eligible theft after delivery within the coverage term—consider adding optional Shipsurance shipping insurance when it is offered at checkout. If you purchased this coverage and a shipping-related issue occurs, review the coverage rules and contact SureCircle first to file a claim or check claim status. Product setup, technical support, product defects and manufacturer-warranty questions remain with SITERWELL. Customer Service U.S. Customer Service Hotline: +1 800-710-7321Monday–Friday, 9:00 AM–6:00 PM (EST)