Typically used for
Temperature
Humidity
Key Features
No hub required! Easy control through the Shelly Smart Control app, as well as various protocols, platforms, and voice assistants
Equipped with the new Shelly chip
Enhanced with a low a consuming e-paper display & built-in clock
Works with type-C USB slot (for faster connection)
Batteries 4 x 1.5 V AA (LR) batteries (not included)
Low battery consumption (Up to 1-year life of the batteries)
Wall mountable
Has an embedded web server and connects to your Wi-Fi network
Device identification
Device name: Shelly H&T Gen3
Device model: S3SN-0U12A
Device SSID: ShellyHTG3-XXXXXXXXXXXX
Device Bluetooth ID: 0x1809
Short description
Shelly H&T Gen3 (the Device) is a Wi-Fi smart humidity and temperature sensor, featuring a large e-paper graphic display.
Main features
Wi-Fi Connectivity: The device can connect to your home Wi-Fi network, allowing you to remotely monitor humidity and temperature data through a smartphone app or other compatible devices.
Large E-Paper Graphic Display: It features a large e-paper graphic display that provides clear and easy-to-read humidity and temperature information.
Digital clock: NTP-synchronized real-time clock.
Integration with Smart Home Platforms: You can integrate the Shelly H&T Gen3 with popular smart home platforms, including Google, Alexa, and Samsung SmartThings. This enables voice control and automation capabilities through these platforms.
USB Type-C Port: It includes a USB Type-C port for powering the device. While it cannot be used to charge the device's batteries, it allows for continuous power through a USB connection.
Bluetooth Connectivity: Bluetooth is available for inclusion purposes, which may be useful during the setup process.
User-Friendly Interface: The device provides a user-friendly interface with a reset button for manual interactions.
Battery Operation: When running on batteries, the device wakes up at set intervals to take measurements of humidity and temperature. It reports changes in data based on predefined thresholds and unconditionally reports its status to the cloud if no reports are made within a specified time.
USB-Powered Operation: When powered via its USB port, the device wakes up more frequently, performs measurements, updates its display, and unconditionally reports data to connected channels.
Environmental Specifications: The device is designed for use in various environments, with an operational temperature range of 0°C to 40°C (32°F to 105°F) and a recommended humidity range of 30% to 70% RH.
Power Supply Options: It can be powered by 4 AA batteries (not included) or a USB Type-C connection.
Wireless Connectivity: The device supports Wi-Fi (802.11 b/g/n) and Bluetooth 4.2 protocols with specified indoor and outdoor range capabilities.
MCU (Microcontroller Unit): The device is equipped with an ESP-Shelly-C38F with 8 MB of flash memory.
These features make the Shelly H&T Gen3 a versatile and convenient device for monitoring humidity and temperature in residential, multi-dwelling units, light commercial, university/college, and other settings, with the added benefits of smart home integration and ease of use.
Main applications
Residential
MDU (Multi Dwelling Units - apartments, condominiums, hotels, etc.)
Light commercial (small office buildings, small retail/restaurant/gas station, etc.)
University/college
Integrations
Amazon Alexa supported capabilities
Yes
Google Smart Home supported traits
Yes
Samsung SmartThings supported capabilities
Yes
Device electrical interfaces
USB Type-C port

To supply power to the Device.
Cannot be used to charge batteries inside the Device.
Connectivity
Wi-Fi
Bluetooth
User interface
Inputs
Reset button (behind the back cover)

Reset button actions
Press briefly:
If the Device is in Sleep mode, puts it in Setup mode.
If the Device is in Setup mode, puts it in Sleep mode.
Press and hold for 5 sec:
If the Device is in Setup mode, enables its access point.
Press and hold for 10 sec:
If the Device is in Setup mode, factory resets the Device.
Outputs
E-paper graphic display

![]() | Current time |
![]() | The Device is in Setup mode. |
![]() | The Device access point is enabled. |
![]() | Humidity readings |
![]() | The Device is receiving over-the-air update. Shows the progress as a percentage instead of the humidity. |
![]() | The Device has reported current readings to the Cloud. If missing, the current readings on the display are not yet reported. In this case, the readings on the display may differ from the ones in the Cloud. |
![]() | Wi-Fi signal strength indicator |
![]() | Indicates battery level. Shows an empty battery when only USB powered. |
![]() | Bluetooth connectivity is enabled. |
![]() | Error while updating the Device firmware |
Measuring and reporting
On batteries
When running on batteries the Device behaves as follows:
Wakes up every minute to do a measurement. If there is a 0.2 °C temperature or 3% humidity difference the screen updates. The default threshold for reporting is a change of 0.5 °C or 5%. If the change is less there will be no report sent.
If for two hours there is no report based on threshold values, the Device unconditionally (disregarding threshold values) reports its status to Shelly Cloud and other connected channels.
Due to self-heating a cool down period of 5 minutes is imposed. During this period the Device would not wake up at all.
On USB power supply
If powered via its USB port the Device will wake up every 5 minutes, perform a measurement, update its screen, unconditionally report to all connected channels, and sleep for 5 minutes.
User initiated report
If the user presses the Reset button (behind the cover) the Device will wake up, perform a measurement, update its screen, unconditionally report to all connected channels, and sleep for 5 minutes.
Quantity | Value |
|---|---|
Physical | |
Size (HxWxD): | 70x70x26 mm / 2.76x2.76x1.02 inch (without stand) |
Weight: | 47 g / 1.66 oz |
Mounting: | With stand (on a horizontal surface) |
Shell material: | Plastic |
Shell color: | White |
Mocha: C:0 M:12 Y:28 K:12 | |
Ivory: C:3 M:4 Y:14 K:8 | |
Black: C:0 M:0 Y:0 K:100 | |
Environmental | |
Ambient working temperature: | 0 °C to 40 °C / 32 °F to 105 °F |
Humidity: | 30 % to 70 % RH |
Max. altitude: | 2000 m / 6562 ft |
Electrical | |
Power supply: | Batteries |
Battery type: | 4 AA (LR6) 1.5 V (not included) |
Estimated battery life: | approx. 1 year (depending on batteries used, temperature and humidity changes, and network connection strength) |
Power supply, USB | Type-C (power adapter and cable not included) |
Sensors, meters | |
Internal-temperature sensor: | No |
Temperature sensor: | Yes |
Humidity sensor: | Yes |
Radio | |
Wi-Fi | |
Protocol: | 802.11 b/g/n |
RF band: | 2401 - 2495 MHz |
Max. RF power: | < 20 dBm |
Range: | Up to 30 m / 100 ft indoors and 50 m / 160 ft outdoors |
Bluetooth | |
Protocol: | 4.2 |
RF band: | 2400 - 2483.5 MHz |
Max. RF power: | < 4 dBm |
Range: | Up to 10 m / 33 ft indoors and 30 m / 100 ft outdoors |
Microcontroller unit | |
CPU: | ESP-Shelly-C38F |
Flash: | 8 MB |
Firmware capabilities | |
Schedules: | No |
Webhooks (URL actions): | 10 with 2 URLs per hook |
Scripting: | No |
MQTT: | Yes |
What are the differences between the different generations of Shelly products?
Each new generation adds more power, memory, and features:
Gen 1 offers basic control;
Gen 2 (Plus Series, Mini Series, Pro Series) adds Bluetooth, scripting, and better security;
Gen 3 improves performance, adds Matter (starting from firmware version 1.6.0 or newer) and advanced monitoring;
Gen 4 offers multi-protocol connectivity, featuring Wi-Fi 6, Bluetooth, Zigbee, and Matter.
Can I control the device via Bluetooth?
No, the protocol is used only for device inclusion, allowing for quick and easy setup through the Shelly Smart Control app.
For bluetooth control it is required to have another Bluetooth device such as Shelly BLU Button or Shelly BLU Motion to interact.
Additionally, Shelly devices can function as a BLE gateway, bridging Shelly BLU devices to your Wi-Fi network.
Is it possible to use the device without a hub?
Yes, Shelly devices (except for Wave devices) operate independently without the need for a hub. They connect directly to your Wi-Fi network, and you can control them via the Shelly Smart Control app, web interface, or through integrations with platforms like Google Home, Alexa, Home Assistant and Samsung SmartThings.
Use cases
The Ultimate Environment Monitor
Ensure the perfect sleeping environment for your baby by monitoring the nursery's temperature and humidity. Set alerts to maintain ideal conditions for a safe and comfortable sleep.
Heating Made Easy: Shelly H&T's Smart Climate Control
Effortlessly transform your old heater into a smart one. By simply connecting your heater to a Shelly Plug, and then linking it with Shelly H&T Gen3, you can create a scene that activates the heater just before the temperature drops.
Intelligent Humidity Control
Maintain a healthy environment in your bathroom with Shelly H&T Gen3. By integrating the sensor with Shelly 1 wired to your bathroom fan, you can automate humidity control with ease.
More Memory, More Power
The Gen3 series ensures the quality and reliability of our devices by using our own powerful Shelly chip. Boasting 8MB of memory, this dramatically improves device performance and efficiency.

















