IFREEQ Publish Smart Liquid Level Sensor With LCD Monitor
Updated: Oct 31
Keep tabs on tank liquid levels effortlessly with this wireless liquid level sensor. Designed for water and other non-corrosive liquids, it supports tank depth ranging from 0.1 m to 5 m. You can view real-time readings directly on its built-in LCD screen, or remotely via the Tuya Smart app over a 2.4GHz Wi‑Fi connection.
The package includes an ultrasonic sensor for installation at the top of your tank and a separate display unit. Pre-paired at the factory, the two modules communicate wirelessly on the 433 MHz RF band, delivering a transmission range of up to 100 meters in open space. The display unit connects to your Wi‑Fi router separately, with an open-area range of roughly 50 meters.
It shows liquid level in both percentage and meters, alongside ambient temperature, alarm logs and historical level trend graphs. Custom high and low level alerts are configurable within the app. You can also enable an audible alarm, tweak its run time between 1 and 60 minutes, or turn the sound off entirely.
Perfect for water tanks, rain harvesting tanks and vessels holding non-corrosive fluids. Note that the sensor needs a pre-drilled mounting opening on the tank and steady 5V power supply. This unit cannot drive a water pump on its own; add a Tuya-enabled relay or switch if you want automatic pump control.
Core Specs
Communication: 2.4 GHz Wi‑Fi + 433 MHz RF
App: Tuya Smart compatible
Measuring range: 0.1–5 m wireless liquid level monitoring
Measuring principle: Non-contact ultrasonic detection (sensor never touches liquid)
Readout: Liquid level shown in percentage and meters
Dual viewing: Local LCD display + remote monitoring via Tuya app
Factory pre-paired sensor & display
RF range (sensor ↔ display): Up to 100 m, open space
Wi‑Fi range (display ↔ router): Up to 50 m, open space
Alerts & Automation
High / low liquid level threshold alarms
Adjustable audible buzzer alarm, with mute option
App records: Alarm history + liquid level trend graphs
Tuya automation support: Hydrate (auto fill) & Drainage (auto empty)
Pump control: Requires an extra Tuya device; no built-in pump relay
Power & Mechanical
- Display/gateway: USB‑C 5V powered, ~96 cm cable included (USB adapter not supplied)
- Sensor power cable: ~90 cm; sensor-to-power lead total length ~180 cm
- Installation: Requires a cutout hole on the tank
- Media compatibility: Water and other non-corrosive liquids
- Sensor power terminal: Non-waterproof
- Sensor rating: IP65
- Display/gateway: Indoor use only, not waterproof
Monitor Display
The bundled display acts both as a local readout panel and the Wi‑Fi gateway for the whole system. You can instantly view live tank levels without opening the mobile app.
Key status indicators shown on the screen:
Pump operation state (On / Off)
Pairing control and device running status
Wi‑Fi network connection status
RF433 sensor link status: flashing = receiving sensor data; no backlight = communication lost
Real-time tank liquid level, shown as percentage (e.g. 60%, 80%, 100%)
Ambient temperature or liquid level percentage
It talks to the ultrasonic sensor over RF433, and connects to the Tuya Smart app via 2.4 GHz Wi‑Fi. The sensor and display come factory pre-paired. The system is ready for use once you complete setup inside the Tuya Smart app.
Dimensions
This smart liquid level sensor kit with LCD monitor features compact sizing for flexible placement. The slim display unit fits neatly inside homes, garages or boiler rooms, while the extended sensor cables simplify mounting near your tank.
Sensor
Housing: 80 × 80 × 41mm
Sensor cable length: approx. 180cm
Power supply cable length: approx. 90cm
Monitor Display
Housing: 62 × 62 × 21mm
USB‑C power cable: approx. 96 cm
Application Scenarios
Household Water Storage
Water Tower
Water Storage for Plants
Grain Storage
Installation
Mount the sensor on the top of your tank. A roughly55 mm diameter mounting hole is required for proper operation.
Installation steps:
Drill an opening in the upper section of the tank
Fit the mounting washer and gasket
Seat the sensor into the hole
Fasten the sensor securely to the tank surface
Extended cables simplify installation and let you route power to a convenient location.
Position the sensor as vertically aligned to the liquid surface as possible. Avoid mounting near tank walls, inlet pipes, or any obstructions that could disrupt ultrasonic readings.
Communication and Range
This kit adopts dual communication: RF433 and 2.4 GHz Wi‑Fi. This separation lets you place the sensor at your tank, while the display gateway sits indoors or in an outbuilding.
The sensor links wirelessly to the gateway over RF433, delivering up to 100 meters of range in open space. This makes it easy to monitor tanks positioned a distance away from your main building.
The gateway connects to your router via 2.4 GHz Wi‑Fi, with an open-area range of up to roughly 50 meters.
Keep in mind: walls, ceilings, metal structures and thick tank lids can shorten the effective wireless range.
What to do if the gateway fails to detect the sensor
If the gateway stops receiving readings from the liquid level sensor, re-pair the two devices.
First, ensure the gateway is already added to your Tuya Smart app, then follow these steps:
Open the gateway device page within the app and navigate to Settings.
Enable 'Pair sub devices'.
The gateway will emit a beep to confirm pairing mode is active.
Press and hold the button on the liquid level sensor for roughly 5 seconds.
Release the button once the green LED begins flashing.
Allow up to 30 seconds for the sensor and gateway to establish the connection automatically.
When pairing completes, the app will show the status as 'Bound'.
Important Installation Notes
For accurate readings, mount the sensor perpendicular to the liquid surface.
The ideal mounting position is near the centre of the tank, clear of inlet and outlet ports and any features that create measurement interference, also known as false echoes.
Avoid placing the sensor close to tank walls, pipes, floats or other obstructions. These objects can reflect ultrasonic signals and trigger incorrect readings.
Keep the measurement zone inside the tank smooth, with no protruding structures within the detection path.
The ultrasonic beam angle is approximately ±15°. Ensure this cone area remains free of obstacles.
Recommended minimum tank diameter for reliable performance:
H = 5 m → D > 2.7 m
H = 4 m → D > 2 m
H = 3 m → D > 1.6 m
H = 2 m → D > 1.1 m
When installing on gently curved surfaces, secure the sensor firmly without over-tightening to avoid straining the housing.
If you get unstable or erratic readings, slightly loosen the mounting screws to relieve mechanical stress on the sensor casing.
The sensor’s power cable joint is not waterproof and must be placed in a dry, sheltered location.
The Monitor Display unit is non-waterproof and designed for indoor use only.
App Home Screen
View key liquid-level and device status data at a glance on the app’s main dashboard.
The dashboard displays:
Current liquid level percentage
Exact liquid height in meters
Ambient temperature at the tank
Live device status
High / low liquid level alarms
Audible alarm toggle: tap **Open Sound / Close Sound** to mute or enable the alert quickly
Recent event and alarm logs
Liquid level trend charts, viewable by day, month or year
When liquid levels go beyond your preset min or max thresholds, the app sends instant push notifications to your phone. You can respond promptly to prevent overfilling or empty tanks.
Measurement & Alarm History
The app logs liquid level readings and alarm records for you to review past events and track tank level variations.
Available records:
Liquid level trend charts, filtered by day, month or year
Historical high and low level alarm logs
Exact timestamp for every recorded event
Quick preview of recent alerts right on the dashboard
This history feature helps you track fluid consumption, spot anomalies and analyse long-term tank level trends.
In‑App Settings
Fine‑tune device behaviour within the app to match your tank specifications and requirements.
Adjustable options:
Max level threshold: 0–100%
Min level threshold: 0–100%
Alarm duration: 1–60 minutes
Sensor installation height: 0–5 m
Maximum liquid depth of the tank: 0–5 m
Pump control: automatic / manual mode
Auto fill (Hydrate) function
Auto drain (Drainage) function
RF433 sensor re‑pairing with gateway
You can also view the sensor‑gateway connection status and toggle individual automation functions on or off directly in the app.
Tank Fill & Drain Automation
Build tank filling and emptying automations via scenes within the Tuya Smart app.
The sensor cannot drive a pump directly. An extra Tuya‑compatible actuator, such as a smart relay or pump controller, is required.
Two automation functions are built in:
Hydrate – Auto tank filling
Drainage – Auto tank emptying
Configurable parameters:
Min liquid threshold (Set Mini): 0–100%
Max liquid threshold (Set Max): 0–100%
Manual or automatic scene trigger mode
Manual Mode
You trigger functions manually from the app:
Enable Hydrate to launch the fill scene
Disable Hydrate to halt filling
Enable Drainage to launch the drain scene
Disable Drainage to stop draining
Automatic Mode
Scenes run automatically according to your preset liquid levels.
For Hydrate (filling):
When the level falls below Set Mini, the fill scene activates automatically.
It stops once the level rises above this threshold, maintaining liquid above your minimum setpoint.
For Drainage (emptying):
When the level rises above Set Max, the drain scene activates automatically.
It stops once the level drops below this threshold.
