SONOFF Hydro DUO – two‑channel smart water valve with flow meter, Zigbee, black (SWV-ZF2E)

The SONOFF Hydro DUO (SWV-ZF2E) is a dual-zone Zigbee 3.0 smart irrigation controller with a built-in flow meter. It can be mounted directly onto an outdoor tap and used to control two separate irrigation circuits, allowing, for example, a lawn and a drip irrigation system to operate according to different schedules. The European SWV-ZF2E version features a 3/4-inch G3/4-14 BSP threaded water connection.

Separate irrigation programs can be configured for the two outputs, with up to 6 schedules per channel and 12 schedules in total. Irrigation can be controlled based on duration or a specified amount of water. The built-in flow meter can measure water flow in the 2–45 l/min range, while irrigation duration and water consumption can be tracked in daily, monthly, and six-month views. The two outputs can be programmed independently, but they cannot operate simultaneously.

The Hydro DUO supports Zigbee 3.0 and BLE proximity communication. With a Zigbee gateway, it can be controlled remotely and integrated into automations, while without a gateway it can be used locally nearby through the BLE proximity connection in the eWeLink app. The device can be powered by four AA batteries or through an external USB-C power supply. Compared to the Hydro ONE Lite, it features two irrigation circuits and a built-in flow meter, allowing irrigation to be controlled not only by duration but also by the amount of water delivered.

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 built around 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 includes DIN rail-mounted devices, energy monitoring solutions, and products suitable for professional installations.

Key Product Features

• Remote irrigation: The water valve for a garden or other irrigated area can be controlled remotely from the app.
• Brass water inlet: The water inlet is made of brass and features a non-slip outer surface to make hand-tightening easier.
• Smart irrigation programs: Up to 6 independent programs can be configured for each output, for a total of 12 programs. Both time-based and water-volume-based irrigation programs can be created.
• Weather-based adjustment: Conditions can be configured based on precipitation probability, humidity, and temperature. When the conditions are met, programs scheduled within the next 24 hours can be skipped automatically.
• Seasonal adjustment: Irrigation duration and water volume can be modified using a monthly multiplier without changing the original programs.
• Dual power supply: The device can be powered by four AA batteries or through an external USB-C power source.
• Safety functions: Notifications can be configured for low battery level, water shortage, water leakage, and frost risk. Child lock disables the local control buttons on the device.
• Irrigation history: Daily, monthly, and six-month data for irrigation duration and delivered water volume can be viewed and downloaded.
• Device sharing and groups: The device can be shared with other eWeLink accounts, while multiple compatible devices can be grouped together.
• Dual communication: Supports Zigbee 3.0 and BLE proximity connectivity. Proximity mode can be used for local control without a Zigbee gateway or when the Zigbee connection is unstable.

Smart Home Protocols and Platform Compatibility

• Zigbee 3.0: The Hydro DUO's primary smart home communication protocol. It can be connected to SONOFF and supported third-party Zigbee gateways.
• BLE proximity: The device can connect directly to a nearby phone running the eWeLink app. In this mode, basic control and configuration functions are available without a gateway.
• eWeLink: With a SONOFF Zigbee gateway, remote control, automations, notifications, and a more complete set of irrigation functions are available in the eWeLink system.
• SONOFF Zigbee gateways: The manufacturer recommends models including ZBBridge-P, ZBBridge-U, NSPanel Pro, and iHost. Additional supported SONOFF coordinators include ZBDongle-P, ZBDongle-E, ZBDongle-M, Dongle Plus MG24, and Dongle Lite MG21.
• Home Assistant and Zigbee2MQTT: Can be integrated directly into Home Assistant with a compatible Zigbee coordinator. According to the manufacturer's compatibility table, manual control, schedules, Rain Delay, seasonal adjustment, history, child lock, and several additional functions are supported.
• Home Assistant and ZHA: Can also be used with ZHA, although the manufacturer's current documentation requires the use of a dedicated Hydro DUO ZHA script. Available functions may differ from those offered in the eWeLink system.
• Amazon Alexa: Can also be connected directly to a compatible Alexa Zigbee hub. The manufacturer lists Echo Show 2nd Gen, Echo Plus 2nd Gen, and Echo 4th Gen models.
• Samsung SmartThings: Direct Zigbee integration is supported with the Aeotec Smart Home Hub V3.
• Google Home: Can be connected to Google Home through cloud integration when used with a SONOFF Zigbee gateway and eWeLink.
• IFTTT: IFTTT integration is supported through the eWeLink platform.
• Matter Bridge: The Hydro DUO is not a native Matter device. It can be bridged to compatible Matter ecosystems through the Matter Bridge function of ZBBridge-U, iHost, or an eWeLink CUBE system using a SONOFF Zigbee Dongle.
• Apple Home: Can also be integrated into Apple Home through a Matter Bridge.

Smart Features

• Two separate irrigation zones: The two outputs can be controlled and programmed independently. Due to the device design, the two channels cannot be opened at the same time.
• Manual irrigation: Both valves can be opened and closed separately from the app or using the local control buttons on the device.
• Time-based irrigation: A valve can be opened for a predefined duration.
• Water-volume-based irrigation: Irrigation can continue until a predefined amount of water has been delivered, based on the built-in flow meter.
• 12 irrigation programs: Up to 6 separate programs can be configured per output, for a total of 12.
• Locally stored programs: Configured irrigation programs are stored locally on the device, so they can still run without a network connection.
• Rain Delay: Upcoming scheduled irrigation can be manually skipped for a defined period.
• Weather-based irrigation: In Zigbee mode, programs scheduled within the next 24 hours can be skipped automatically based on precipitation probability, humidity, and temperature. The function relies on third-party weather data.
• Seasonal adjustment: Programmed irrigation duration and water volume can be modified using a monthly multiplier.
• Flow measurement: The built-in flow meter detects water flow in the 2–45 l/min range.
• Irrigation history: Daily, monthly, and six-month charts for irrigation duration and water volume can be viewed and downloaded.
• Water shortage detection: If the flow remains below 5 l/min for the configured period, a water shortage alarm can be triggered. The valve can also be configured to close in this situation.
• Leak detection: If the device continues detecting water flow beyond the configured period after the valve has closed, it can send a leak alarm.
• Frost alert: A local minimum temperature threshold can be configured, below which the eWeLink system sends a warning.
• Low battery warning: Battery level can be monitored, and a notification can be configured for low battery status.
• Child lock: When enabled, the local control buttons no longer operate the valves, while app-based control remains available.
• Automations: eWeLink scene conditions can include valve status, irrigation duration, delivered water volume, battery level, water shortage, and leak detection, among others.
• Device sharing: Hydro DUO control can be shared with other eWeLink accounts.
• OTA firmware update: The firmware can be updated wirelessly. If an update fails, the manufacturer recommends using BLE proximity mode.

Power Supply and Valve Operation

• Battery power: 4 × 1.5 V AA batteries in a 2S2P configuration, with a nominal supply voltage of 3 V DC.
• USB-C power supply: An external 5 V DC, 1 A power source can be used. The manufacturer's detailed documentation specifies a supply voltage of 4.5–5.5 V and a power source capable of delivering more than 0.4 A.
• Power supply priority: If batteries and USB-C power are connected at the same time, the device uses USB-C as the primary power source.
• Batteries: AA batteries are not included in the package.
• Expected battery life: Approximately one year under normal use. The manufacturer's test was based on two 30-minute irrigation sessions per day. With continuous flow measurement, battery life may decrease to approximately one month.
• Solar power: A solar panel with its own battery can be connected to the USB-C input.
• Controlled irrigation circuits: The device has two separate outputs. The two channels can be programmed independently but cannot operate simultaneously.
• Operating water pressure: 0.06–0.8 MPa.
• Operating water temperature: 5–40 °C.
• Flow meter: Built-in, with a 2–45 l/min measurement range.
• Water inlet: Brass construction.
• Thread standard: The European SWV-ZF2E version uses a 3/4-inch G3/4-14 BSP connection.
• Flow direction: The inlet and outlets cannot be reversed; the device must be installed according to the specified direction of water flow.
• Local control buttons: The two outputs can also be opened and closed locally. The buttons can also be used for pairing, disabling child lock, and factory reset.

Technical Specifications

• Product name: Hydro DUO
• Product series: Hydro Series
• Product type: Dual-channel Zigbee smart water valve with flow meter
• Model: SWV-ZF2E
• MCU: TLSR8258F1KAT32
• Input: 3 V DC, 4 × 1.5 V AA batteries, 2S2P / USB-C 5 V DC, 1 A
• Wireless connectivity: Zigbee 3.0 and BLE
• Protection rating: IP65
• Operating water pressure: 0.06–0.8 MPa
• Flow meter measurement range: 2–45 l/min
• Water connection: 3/4-inch, G3/4-14 BSP
• Dimensions: 121 × 132 × 67 mm
• Colour: Black and orange
• Enclosure material: ABS
• Operating temperature: 0–50 °C
• Operating water temperature: 5–40 °C
• Operating humidity: 5–95% relative humidity, non-condensing
• Maximum operating altitude: Below 2000 m
• Maximum wireless communication range: 130 m in open space
• Certifications: CE, FCC, RoHS

Additional Features

• IP65 protection: Fully protected against dust ingress and protected against water jets from any direction.
• Vertical installation: The manufacturer recommends vertical installation because horizontal mounting may increase flow measurement error.
• Pressure loss: Due to the built-in flow meter, the manufacturer states that the device may reduce water pressure by approximately 10%.
• Winter storage: In freezing conditions, the manufacturer requires draining any remaining water from the device, removing the valve, and storing it indoors.
• Outdoor USB-C use: When using an external power source, the water resistance of the complete system also depends on the USB-C cable used; the manufacturer recommends a waterproof silicone cable for outdoor use.
• Screwed battery compartment: The battery compartment cover can be secured with a screw to maintain the device's protection rating.
• Not recommended for drinking water: The manufacturer primarily designed the Hydro DUO for garden irrigation using mains water and does not recommend connecting it to a drinking water system.
• Compared to Hydro ONE Lite: The Hydro DUO features two irrigation outputs and a built-in flow meter. This allows two separate zones to be programmed and irrigation to be controlled based on a specified water volume as well as duration.