Shelly Flood S Gen4 Smart Flood Sensor

Shelly Flood S Gen4 Smart Flood Sensor
A faulty valve, a leaky gasket in the dishwasher, or water slowly leaking from under the washing machine often go unnoticed for hours. The Shelly Flood S Gen4 allows you to detect the problem before it leads to damp walls, wet floors, or damage to your appliances. The sensor uses three large detection fields made of stainless steel, allowing it to quickly respond to both regular water and low-conductivity liquids, such as air conditioning condensate or distilled water. Wi-Fi, Bluetooth, and Zigbee connectivity, support for the Matter standard, and a battery life of approximately 2 years make this device an integral part of a modern smart home system.


A Discreet Guardian for Your Home
Most places where leaks occur are out of sight. The Shelly Flood S Gen4 has a compact design measuring 23 × 77 mm—it can be discreetly tucked under a washing machine, dishwasher, or refrigerator. Even if a minor leak occurs, the device will immediately detect the threat and send a notification, allowing you to respond quickly no matter where you are. Its IP67 rating further enhances its resistance to harsh conditions and accidental splashes.


A smart home that responds to threats
The Shelly Flood S Gen4 can not only immediately send an alert to your smartphone but also trigger pre-configured automations. When paired with a compatible smart valve, the system can automatically shut off the water supply, reducing the risk of costly damage. Importantly, these automations operate locally, so protection remains active even without cloud access.


Two operating modes and an alarm tailored to the situation
The Shelly Flood S Gen4 sensor isn’t just for indoor use. You can choose between two operating modes: flood detection and rainfall detection. In the latter case, the device can become part of a smart home management system and respond to changing weather conditions. When it starts to rain, the system can pause garden watering, extend awnings, or close skylights. Additionally, three alarm profiles are available—Intense, Normal, and Economic—and the built-in buzzer immediately alerts you to a detected threat.


Unlimited Connectivity and Broad Compatibility
Support for the Matter standard enables integration with various platforms, and compatibility with the Shelly Smart Control app and popular home automation systems allows you to create complex action scenarios. The device works with Amazon Alexa, Google Smart Home, Samsung SmartThings, and Home Assistant, among others. Wi-Fi 6, Bluetooth 5 LE, and Zigbee 3.0 connectivity provide great flexibility in configuration and allow you to tailor communication methods to your individual needs.


Protection That Works Every Day
The sensor can be used in apartments, single-family homes, multi-family buildings, commercial facilities, farms, educational institutions, and public buildings. It is ideal for monitoring areas under sinks, near water heaters, close to filters and valves, as well as next to toilets, washing machines, and dishwashers.


Included in the set
Flood sensor
CR123A battery


General


Manufacturer
Shelly
Model
Flood S Gen4
Dimensions (H × D)
23 × 77 mm
Weight
50 g (without battery) / 70 g (with battery)
Mounting method
On a flat surface
Housing material
Plastic
Housing color
White


Environmental specifications


Operating temperature
From -20°C to 40°C
Humidity
30% to 100% RH
Maximum operating altitude
2000 m


Electrical specifications


Power supply
Battery-powered
Battery type
1 × CR123A (included)
Estimated operating time
Approximately 2 years (depending on battery type, usage intensity, and network signal strength)


Sensors and Measurements


Water Detection
Yes


Wi-Fi Connectivity


Standard
802.11 b/g/n/ax
Frequency Band
2401–2483 MHz
Maximum RF Transmission Power
< 20 dBm
Range
Up to 30 m indoors and up to 50 m outdoors (depending on local conditions)


Bluetooth Connectivity


Standard
Bluetooth 5 LE
Frequency Band
2402–2480 MHz
Maximum RF Transmission Power
< 20 dBm
Range
Up to 10 m indoors and up to 30 m outdoors (depending on local conditions)


Zigbee connectivity


Standard
802.15.4
Frequency band
2405–2480 MHz
Maximum RF transmission power
< 20 dBm
Range
Up to 100 m indoors and up to 300 m outdoors (depending on local conditions)


Microcontroller


Processor
ESP-Shelly-C68F
Flash memory
8 MB


Software features


Schedules
No
Webhooks (URL actions)
10, with the ability to assign 2 URLs to each event
Script support
No
MQTT
Yes
UDP
Yes
KVS (Key-Value Store)
Yes