Sonoff Thermostat Core – Room thermostat, Zigbee, Bluetooth, white (TP-WGZBA)

The SONOFF Thermostat Core TP-WGZBA is a 100–240 V AC powered Zigbee 3.0 smart thermostat for controlling hydronic underfloor heating systems and boilers. It features an active L Out relay output with a maximum load capacity of 3 A for hydronic underfloor heating actuators, as well as a separate COM/NO dry contact output for switching boilers with a potential-free thermostat input. Because of the 3 A load limit, it is not suitable for directly switching electric underfloor heating.

The temperature can be controlled between 5 and 30 °C. Three separate weekly heating programmes can be stored, with all seven days configurable in each programme and up to 12 temperature periods per day. Automatic, manual and frost protection modes, Boost mode, temporary temperature override, adjustable hysteresis and two types of open-window detection are available. Saved programmes are executed locally by the built-in real-time clock, so they continue running even during a temporary loss of Zigbee connectivity.

The thermostat requires a Zigbee gateway for remote control. It is primarily designed for use with the eWeLink system, but it can also be integrated with Home Assistant through Zigbee2MQTT, while ZHA currently requires a separate device handler script for full functionality. A dedicated driver is available for SmartThings. The device itself is not a Matter device, but it can be exposed to Apple Home through a compatible SONOFF Matter Bridge.

About SONOFF

SONOFF manufactures smart home devices, relay modules, energy meters, wall switches, Zigbee sensors, control panels, gateways and various electrical installation accessories. Its product range includes devices using Wi-Fi, Zigbee, Matter and LAN communication.

SONOFF devices are primarily based on the eWeLink platform, but many products can also be integrated with Home Assistant, Zigbee2MQTT, ZHA, SmartThings, Alexa, Google Home and other smart home systems. In addition to residential smart home solutions, the manufacturer's range also includes DIN rail-mounted devices, energy monitoring solutions and products suitable for professional installation.

Key product features

• Dual output: Features a switched output supporting loads up to 3 A and a separate potential-free dry contact output. It can be used with both hydronic heating systems and boilers.
• Three flexible heating schedules: Three independent temperature control programmes are available, each supporting a full weekly schedule with up to 12 periods per day. Different weekday, weekend, holiday or family routines can be selected without reconfiguring the programmes.
• Minimalist design with smart control: The rounded white design is complemented by a physical rotary control for local temperature adjustment. The built-in presence sensor wakes the display when you approach and turns it off when you leave, while display brightness can also be adjusted.
• More accurate room temperature: A remote temperature sensor connected to the same gateway can be used as the temperature reference for regulation, helping reduce measurement errors caused by thermostat self-heating and installation location.
• Smart open-window detection: Supports both automatic open-window detection and linking with a SONOFF door/window sensor. Heating can be paused automatically when an open window is detected.

Smart home protocols and platform compatibility

• Zigbee 3.0: Uses IEEE 802.15.4 Zigbee communication. A compatible Zigbee coordinator or gateway is required for smart home functions.
• eWeLink: The factory platform is eWeLink. The app can be used to configure temperature, operating modes, weekly programmes, Boost mode, frost protection, display settings, radar detection, open-window detection and additional thermostat parameters.
• SONOFF Zigbee gateways: The manufacturer lists models including ZBBridge-P, ZBBridge-U, NSPanel Pro and iHost as compatible gateways. It can also be used with SONOFF Zigbee USB coordinators in open-source systems.
• Home Assistant and Zigbee2MQTT: Can be integrated with Home Assistant through Zigbee2MQTT. Zigbee2MQTT 2.14.0 or newer is required for TP-WGZBA support.
• MQTT: The thermostat itself is not a native MQTT device. When Zigbee2MQTT is used, MQTT communication is provided by the Zigbee2MQTT middleware.
• Home Assistant ZHA: The native TP-WGZBA ZHA device handler has not yet been merged into the official ZHA Device Handlers release. Full functionality requires manual installation of the separate TP-WGZBA ZHA script provided by SONOFF; without it, only some functions are available.
• SmartThings: A separate SONOFF SmartThings Edge driver is required for direct Zigbee integration. The manufacturer also lists the Aeotec Smart Home Hub V3 as a compatible SmartThings gateway.
• Amazon Alexa: Operating mode and target temperature can be controlled through eWeLink integration. The manufacturer also documents direct Zigbee use with certain Echo models featuring a built-in Zigbee hub, although the available functionality may be more limited than with eWeLink.
• Google Home: Thermostat operating mode and target temperature can be controlled through eWeLink integration.
• Apple Home: The TP-WGZBA is not a native Matter device. It can be exposed to Apple Home using a compatible SONOFF Matter Bridge, such as Bridge-M, or a suitable eWeLink CUBE solution.

Smart features

• Remote temperature control: The current target temperature can be adjusted between 5 and 30 °C.
• Current status: The eWeLink app shows whether the thermostat is currently heating or idle.
• Current temperature: Displays either the temperature measured by the thermostat or the value from the selected external temperature sensor.
• Automatic mode: Temperature control follows the active weekly programme.
• Manual mode: The desired temperature can be set directly on the device or from the app.
• Frost protection mode: Maintains a low protective temperature. The default frost protection value is 5 °C, and the threshold can be adjusted in the app.
• Boost mode: A temporary intensive heating mode can be started for a configurable duration.
• Temporary temperature override: A fixed temperature can be set for a defined period, after which the thermostat returns to the previous operating mode.
• Three weekly programmes: A total of three separate programmes can be saved, with one selected as active.
• 12 periods per day: Each of the three programmes can be configured separately for all seven days of the week, with up to 12 temperature periods per day.
• Locally executed schedules: The device features a built-in real-time clock and stores saved heating schedules locally. Programmes continue to run even if the Zigbee connection is temporarily interrupted, provided that the thermostat remains powered.
• Six-month history: In the eWeLink system, target temperature, actual temperature and heating activity can be viewed for up to 6 months.
• Automatic open-window detection: If the temperature drops by more than 1.5 °C within 5 minutes while heating, the thermostat detects an open window and pauses heating.
• Door/window sensor-based open-window detection: When linked with a SONOFF SNZB-04, SNZB-04P or SNZB-04PR2 sensor, heating can stop immediately when a door or window is opened. The sensor must be connected to the same SONOFF Zigbee gateway.
• Automatic recovery: After open-window detection, heating resumes when the window is closed or when the temperature stabilises.
• Remote temperature source: Data from another SONOFF Zigbee temperature sensor can be used as the control reference instead of the thermostat's own sensor. Supported models include SNZB-02, SNZB-02P, SNZB-02D, SNZB-02WD, SNZB-02LD, SNZB-02B and SNZB-02M.
• Temperature calibration: Local temperature measurement can be corrected with a manual offset, for example to compensate for differences caused by thermostat placement or self-heating.
• Adjustable hysteresis: Separate heating start and stop thresholds can be used. The configurable range is from -2.6 to +2.6 °C.
• Radar-based display wake-up: The built-in radar sensor automatically switches on the display when someone approaches and turns it off after they move away.
• Adjustable radar sensitivity: Low, medium and high sensitivity levels are available, corresponding to detection distances of approximately 0.3 m, 0.6 m and 1 m.
• Radar Do Not Disturb mode: Automatic display wake-up can be disabled during a specified time period.
• Display brightness: Active and standby brightness can be adjusted separately across levels 0–8.
• Night display mode: A separate time period and brightness level can be configured for night-time operation.
• Child lock: The physical rotary control and local operation can be locked from the app or by holding the central button for 3 seconds.
• External floor temperature sensor: A wired 10 kΩ NTC sensor with B3950 characteristic can be connected to the thermostat.
• Floor overtemperature protection: When an external NTC sensor is used, floor temperature can be monitored and heating can stop automatically if the configured limit is exceeded.
• Central TRV control: Thermostatic radiator valves connected to the same compatible SONOFF Zigbee gateway can be controlled together from the wall thermostat. Target temperature, operating mode and programme changes can be synchronised with linked TRVs.
• Device groups: Multiple compatible devices can be organised into an eWeLink group and controlled together.
• Sharing: Thermostat access can be shared with other eWeLink accounts.
• Push notifications: App notifications can be enabled for device alerts and open-window detection.
• Smart scenes: Open-window status, heating status and current temperature can be used as automation conditions, among others. Operating mode or a target temperature between 5 and 30 °C can be set as automation actions.

Electrical features

• Supply voltage: 100–240 V AC, 50/60 Hz.
• Neutral wire: Both L live and N neutral conductors must be connected for operation.
• Active relay output: The L Out terminal is a switched mains live output with a maximum load capacity of 3 A.
• Load type: The 3 A rating of the active output applies to resistive loads.
• Hydronic underfloor heating actuators: Compatible 100–240 V AC actuators with a total load of up to 3 A can be controlled directly from the L Out output.
• NC and NO actuators: By default, the thermostat is configured for normally closed (NC) actuators. In the eWeLink app, the output control logic can also be changed for normally open (NO) actuators.
• Boiler dry contact output: Features a separate dry contact relay output for ON/OFF control of boilers with a potential-free thermostat input.
• COM / NO terminals: The physical terminals of the dry contact output are COM and NO. There is no separate NC terminal.
• Dry contact switching: The COM and NO contacts are electrically isolated from the thermostat's 100–240 V AC power supply.
• Dry contact safety: According to the manufacturer, mains voltage must not be connected directly to the COM/NO terminals; they are intended for a boiler's potential-free thermostat input.
• Two separate outputs: Features one active L Out load output and one separate COM/NO dry contact output.
• External NTC input: Two Sensor terminals are provided for a wired 10 kΩ NTC temperature sensor with B=3950 K characteristic.
• Electric underfloor heating: The manufacturer does not recommend directly switching electric underfloor heating, as these loads typically exceed the thermostat's 3 A output limit.
• Recommended wire cross-section: 0.2–3.5 mm², or 24–12 AWG.

Technical specifications

• Product series: SONOFF Thermo Series
• Product type: Zigbee smart thermostat
• Model: TP-WGZBA
• Wireless connection: Zigbee 3.0
• Zigbee standard: IEEE 802.15.4
• Application: Hydronic heating system
• Installation: Flush-mounted wall installation
• Rated parameters: 100–240 V AC, 50/60 Hz, max. 3 A
• Hydronic heating actuator output: Active relay output
• Maximum active output load: 3 A
• Active output load type: Resistive load
• Boiler control output: Passive, potential-free dry contact
• Boiler control terminals: COM, NO
• Temperature setting range: 5–30 °C
• Radar detection distance: Approx. 0.3 m at low sensitivity, approx. 0.6 m at medium sensitivity and approx. 1 m at high sensitivity
• External NTC floor sensor: 10 kΩ NTC, B-value 3950 K
• Dimensions: 86 × 86 × 45.5 mm
• Flush-mounted section depth: 31.5 mm
• Mounting screw spacing: 60 mm
• Operating temperature: 0–50 °C
• Operating humidity: Up to 90% RH, non-condensing
• Colour: SONOFF white
• Housing material: PC
• Rated impulse voltage: 4 kV
• Recommended wire cross-section: 24–12 AWG, 0.2–3.5 mm²
• Pollution degree: II
• Automatic operating cycles: 10,000 cycles
• Control action type: 1.B
• Maximum operating altitude: 2000 m
• Certifications: CE, RoHS