Leak detection / Device
Water Leak Sensor 6
Hub sold separately
Pack options
1 sensor · rope included
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Water protection
Catch leaks. Protect your home.
A sensor by your water heater can alert your phone when water appears. Add automatic shutoff to help limit the damage.
Example phone alertWater detectedWater heater sensor
Illustrative setupDetect → Alert → Optional shutoff
A leak by the water heater. An alert wherever you are. An online hub sends the alert. Add a compatible valve and configure the sensor to close it automatically.How the system works
How it works
Put sensors where leaks start. Choose alerts, or add a valve that can respond for you.
- 01Detect
Place a sensor by the water heater, under a sink or beside the washing machine. It detects water where it is placed.
- 02Alert
Your connected hub sends a phone alert, so you can act even when you’re away. Choose sensors with an alarm for a warning at home, too.
- 03Respond
Add a compatible shutoff kit and configure it to close your water valve when a paired sensor detects a leak. Test it after setup.
Choose a starting point.
Your options
What would you like to do?
How would you like to add shutoff?
Turn your existing valve, or have a new motorized valve installed.
Check three things on your main shutoff valve.
- A quarter-turn ball valve. Its lever turns about 90°. A round, multi-turn handle needs a different solution.
- A valve that works. It must turn smoothly and shut off the water fully. An operator cannot repair a worn or stuck valve.
- Room for the operator. Check valve size, shaft or handle dimensions, mounting space and full handle travel against the selected product.
If all three fit, start with an existing-valve kit. Replacing a valve or planning plumbing work? Choose a new inline valve.
Still unsure? Ask support about fit with photos of your valve and the space around it.
Leak alerts
Newest · sensing rope + humidity
Detect water along an 11.5 ft sensing rope, with temperature and humidity alerts. This sensor has no built-in audible alarm.
YS7984 · Hub: YS1603
Keep the body dry; lay the rope along a leak path. No plumbing work.
Setup contents
- 1 Water Leak Sensor 6, with 2 AA lithium batteries
- 1 sensing rope, 11.5 ft (3.5 m)
- 1 YoLink Hub, purchased separately
Sensor + hub total£99.00
New to YoLink? Buy both. Have a hub? Buy only the sensor.
Body contacts + audible alarm
Detect drips and pooling water at the sensor body, with an audible alarm and advanced temperature alerts.
YS7986 · Hub: YS1603
Place by an appliance or fixture. No plumbing work.
Setup contents
- 1 Water Leak Sensor 5, with 2 AA lithium batteries
- 1 YoLink Hub, purchased separately
Sensor + hub total£85.00
New to YoLink? Buy both. Have a hub? Buy only the sensor.
For four risk points, with local alarms
Cover four risk points, with an alarm at each sensor and a low-temperature freeze warning.
YS1603 · YS7906
No plumbing work.
Setup contents
- 1 YoLink Hub with power and Ethernet cables
- 4 Water Leak Sensors 4, with batteries
Hardware price£89.00
Shop this kit →Probe tip + audible alarm
Reach a specific leak point with the probe cable while keeping the sensor body dry. Includes an audible alarm.
YS7904W · Hub: YS1603
Keep the body dry; place the probe at the leak point. No plumbing work.
Setup contents
- 1 Water Leak Sensor 3, with batteries and probe cable
- 1 YoLink Hub, purchased separately
Sensor + hub total£60.00
New to YoLink? Buy both. Have a hub? Buy only the sensor.
Detect water along a cable
Use the sensing ropes along an appliance or leak path. Each sensor also has an audible alarm.
YS1603 · YS7904G
Keep the bodies dry; lay the ropes along leak paths. No plumbing work.
Setup contents
- 1 × YoLink Hub (YS1603)
- 4 × Water Leak Sensor 2 (YS7904G)
Hardware price£124.00
Shop this kit →Simple phone alerts
Choose this if phone alerts are enough. These sensors do not have a built-in alarm.
YS1603 · YS7903
No plumbing work.
Setup contents
- 1 YoLink Hub
- 4 Water Leak Sensors 1
Hardware price£85.00
Shop this kit →Shutoff with an existing valve
Recommended for a compatible existing valve
Automatic water shutoff / Complete system
Controller 2 + EVO starter kit
Hub included
Pack options
Hub + 3 leak sensors
Get leak alerts and add automatic shutoff without cutting the pipe. The EVO attaches to the valve shaft.
YS1603 · YS7903 · YS5003S · YS5004
Check ball-valve compatibility and mounting clearance. Adapter or AA-battery power.
Setup contents
- 1 × Valve Controller 2 (YS5003S)
- 1 × EVO Valve Operator (YS5004)
- 1 × YoLink Hub (YS1603)
- 3 × Water Leak Sensor 1 (YS7903)
Hardware price£328.00
Shop this kit →Battery-powered controller
Automatic water shutoff / Complete system
X3 + Bulldog starter kit
Hub included
Pack options
Hub + 4 leak sensors
Choose X3 lithium power and a Bulldog operator that turns the existing valve handle.
YS1603 · YS7903 · YS5001S · BDOG
Requires a working ball valve and full handle clearance. Replaceable lithium battery pack.
Setup contents
- 1 × YoLink Hub (YS1603)
- 4 × Water Leak Sensor 1 (YS7903)
- 1 × Bulldog Valve Robot
- 1 × X3 Valve Controller (YS5001S)
- X3 controller lithium battery
Hardware price£474.00
Shop this kit →Plug-in controller + handle operator
Automatic water shutoff / Complete system
Controller 2 + Bulldog starter kit
Hub included
Pack options
Hub + 3 leak sensors
The Bulldog turns your existing handle; Controller 2 supports adapter or AA-battery power.
YS1603 · YS7903 · YS5003S · BDOG
Check ball-valve compatibility, handle clearance and manual-clutch access.
Setup contents
- 1 × YoLink Hub (YS1603)
- 1 × Valve Controller 2 (YS5003S)
- 3 × Water Leak Sensor 1 (YS7903)
- 1 × Bulldog Valve Robot
- Controller power adapter and 4 AA batteries
Hardware price£389.00
Shop this kit →Shutoff with a new valve
Recommended when installing a new valve
Automatic water shutoff / Device
X3 Smart Motorized Valve
Hub + sensors in the second product below
Pack options
Valve hardware only
A new inline valve with its controller built in. Add the hub-and-sensor kit below for leak-triggered shutoff.
YS5012 + YS1603 · YS7906
Plumbing installation required. Check pipe size and connections. Replaceable lithium battery.
Setup contents
- 1 X3 Smart Motorized Valve with integrated controller
- 1 YoLink Hub + 4 Water Leak Sensors 4 (second product below)
Hardware totalFrom £272.00
AA-battery valve
Automatic water shutoff / Device
Smart Motorized Valve
Hub + sensors in the second product below
Pack options
Valve hardware only
An inline valve with built-in control, powered by two AA batteries.
YS5002 + YS1603 · YS7906
Plumbing installation required. Check pipe size and connections. Two AA batteries.
Setup contents
- 1 Smart Motorized Valve with integrated controller
- 1 YoLink Hub + 4 Water Leak Sensors 4 (second product below)
Hardware totalFrom £272.00
Separate controller
Automatic water shutoff / Device
Controller 2 + inline valve
Hub + sensors in the second product below
Pack options
Valve hardware only
Choose this when you prefer a separate Controller 2 with adapter or AA-battery power.
YS5003S · DN15–DN50 family + YS1603 · YS7906
Plumbing installation required. Choose pipe size and material on the product page.
Setup contents
- 1 motorized inline valve + Valve Controller 2
- 1 YoLink Hub + 4 Water Leak Sensors 4 (second product below)
Hardware totalFrom £247.00
Water use and shutoff
Recommended for a 1-inch installation
Leak detection / Starter kit
FlowSmart All-in-One
SpeakerHub included
Pack options
1-inch · SpeakerHub + 3 sensors
See water use, configure flow-based shutoff rules and detect water near appliances with one starter kit.
YS5018 · YS1604 · YS7906
Plumbing installation required; this kit is for 1-inch pipe. Replaceable lithium battery.
Setup contents
- 1 FlowSmart All-in-One 1-inch meter, valve and integrated controller
- 1 SpeakerHub
- 3 Water Leak Sensors 4
Hardware price£407.00
Shop this kit → Other pipe sizes →Separate meter and valve
Water level & flow / Complete system
FlowSmart Control
Hub + sensors in the second product below
Pack options
Meter + valve hardware
Choose separate inline components when that layout better suits your plumbing.
YS5006 + YS1603 · YS7906
Plumbing installation required. Allow room for the meter, valve, controller and cables. Adapter and AA power.
Setup contents
- 1 water meter + motorized valve + dedicated FlowSmart controller
- 1 YoLink Hub + 4 Water Leak Sensors 4 (second product below)
Hardware totalFrom £587.00
- AppliancesWashing machine, dishwasher, refrigerator supply line
- FixturesSinks, toilets, and supply connections
- EquipmentWater heater, HVAC drain, sump area
- Hard-to-check spacesBasement, crawlspace, second home, or remote property
Compare products
Looking for a particular feature? Open the full comparison. Every model is included, with the newest listings first.
Compare all models Leak sensors · controllers · valves & flow monitoring+
Leak sensors
An online YoLink hub is required for app alerts. Prices are for one sensor; hub kits are in the starting-point chooser.
Scroll across to compare all 6 models.
| Feature |  Sensor 6 YS7984£70.00 · 1 sensorShop now |  Sensor 5 YS7986£56.00 · 1 sensorShop now |  Sensor 4 YS7906£25.00 · 1 sensorShop now |  Sensor 3 YS7904W£31.00 · 1 sensorShop now |  Sensor 2 YS7904G£31.00 · 1 sensorShop now |  Sensor 1 YS7903£21.00 · 1 sensorShop now |
|---|---|---|---|---|---|---|
| Detection | Along the included 11.5 ft (3.5 m) sensing rope | Top and bottom of the body | Top and bottom of the body | At the end of a probe cable | Along a compatible sensing rope | Top and bottom of the body |
| Audible alarm | No built-in sounder · flashing LED indication | Yes | Yes | Yes | Yes | No built-in sounder |
| Temperature alerts | High and low thresholds, plus rapid-rise and rapid-drop alerts | High and low thresholds, plus rapid-rise and rapid-drop alerts | Adjustable low-temperature freeze warning | No · auxiliary temperature display only | No · auxiliary temperature display only | No · auxiliary temperature display only |
| Humidity alerts | High and low humidity limits | No | No | No | No | No |
| Batteries | 2 AA lithium | 2 AA lithium | 2 AAA alkaline | 2 AAA alkaline | 2 AAA alkaline | 2 AAA alkaline |
| Placement | Indoor body; keep it dry. Only the sensing rope is waterproof | IP67 housing; avoid prolonged submersion | IP66 housing | IP50 body; keep it dry | IP50 body; keep it dry | IP68 housing |
More sensor specifications
Scroll across to compare all 6 models.
| Feature | Sensor 6 YS7984£70.00 · 1 sensorShop now | Sensor 5 YS7986£56.00 · 1 sensorShop now | Sensor 4 YS7906£25.00 · 1 sensorShop now | Sensor 3 YS7904W£31.00 · 1 sensorShop now | Sensor 2 YS7904G£31.00 · 1 sensorShop now | Sensor 1 YS7903£21.00 · 1 sensorShop now |
|---|---|---|---|---|---|---|
| Request a new reading now | Yes · Refresh from the app; see last-update time | Yes · Refresh from the app; see last-update time | Event and periodic reports; immediate refresh is not documented | No · updates on events, check-ins or a SET-button press | No · updates on events, check-ins or a SET-button press | No · updates on events, check-ins or a SET-button press |
| Remote Find Device beep | No beep · Find Device flashes the status LED | Yes · repeating beeps with Find Device | Not documented in the current guide | No | No | No · no built-in sounder |
| Set alarm timing | Repeat reminders + initial delay from 2 seconds to 4 hours | Repeat reminders + initial delay from 2 seconds to 4 hours | Repeat-reminder interval | Repeat-reminder interval | Repeat-reminder interval | Repeat-reminder interval |
| Keep the body accessible | Body stays dry and accessible; rope goes along the leak path | Body goes at the detection point | Body goes at the detection point | Body can stay away from the wet point | Body can stay away from the wet point | Body goes at the detection point |
| Body size · L × W × D | 70 × 70 × 24 mm | 85.5 × 42 × 31.4 mm | 62 × 62 × 28 mm | 62 × 62 × 22 mm | 62 × 62 × 22 mm | 62 × 62 × 23.5 mm |
Leak events are reported when detected; periodic check-ins are not a delay before reporting a leak. Auxiliary temperature readings on Sensors 1–3 are occasional readings, not temperature alarms. Features depend on the model, compatible firmware, hub and app.
Controllers
For compatible valve operators and inline valves. Prices are for the controller only; the valve or operator, hub and sensors are separate.
Scroll across to see all models.
| Feature |  X3 Controller YS5001SFrom £158.00Shop now |  Controller 2 YS5003SFrom £158.00Shop now |  Controller 1 YS4909From £73.00Shop now |
|---|---|---|---|
| Power | Battery only · replaceable lithium pack | Plug-in adapter, 4 AA alkaline, or both | Battery only · 4 AA alkaline |
| Power outage | Operates from its working lithium pack | Battery backup if working batteries are installed; adapter alone stops with power loss | Operates from its working AA batteries |
| Position feedback | Yes · with a compatible feedback-equipped operator/valve and correct wiring | Yes · with a compatible feedback-equipped operator/valve and correct wiring | No feedback connection · app position can be wrong after manual operation |
Use matched YoLink-approved hardware. Position feedback needs a compatible feedback-equipped operator or valve and correct wiring; it reports the mechanism’s position, not whether a worn valve seals. FlowSmart Control includes its own dedicated meter/valve controller.
Valves & flow monitoring
Compare existing-valve operators, inline valves and FlowSmart together. Kit prices include the matched controller. Model codes identify the hardware family; DN-series codes vary by pipe size and material.
Scroll across to compare all 8 models.
| Feature |  X3 Smart Motorized Valve YS5012From £183.00Shop now |  FlowSmart All-in-One YS5018From £292.00Shop now |  FlowSmart Control YS5006From £498.00Shop now |  Motorized inline valve DN15–DN50 seriesKit from £158.00Shop now X3 kit ↗ |  EVO YS5004Kit from £292.00Shop now X3 kit ↗ |  Bulldog BDOGKit from £365.00Shop now X3 kit ↗ |  Smart Motorized Valve YS5002From £183.00Shop now |  Basic operator YS4909FKit from £93.00Shop now |
|---|---|---|---|---|---|---|---|---|
| Installation type | Inline · plumbing required | Inline · plumbing required | Inline · plumbing required | Inline · plumbing required | Existing ball valve | Existing ball valve | Inline · plumbing required | Existing ball valve |
| Difference | Valve with built-in control and lithium power | Meter, valve and controller in one assembly | Separate meter, valve and dedicated controller | Valve connected by cable to a separate controller | Attaches to the valve shaft; remove the handle | Turns the existing handle; manual clutch | Valve with built-in control and AA power | Turns the existing handle; check bracket and axis alignment |
| Separate controller required? | No · built in | No · built in | Yes · dedicated meter/valve controller included | Yes · Controller 2 or X3 | Yes · Controller 2 or X3 | Yes · Controller 2 or X3 | No · built in | Yes · Controller 1 in the linked kit |
| Flow monitoring | No | Yes · usage readings and configured flow-based shutoff rules | Yes · usage readings and configured flow-based shutoff rules | No | No | No | No | No |
| Power | Replaceable lithium battery pack | Replaceable lithium battery | Plug-in adapter and 4 AA batteries | Through the matched controller | Through the matched controller | Through the matched controller | 2 AA batteries | Through the matched controller |
Operators need a compatible ball valve that turns smoothly and shuts off fully. Inline models require plumbing installation. Check size, fit and included components on the product page.
Before you buy
FAQ
Do I need a YoLink hub?
For app access and remote alerts, choose a compatible YoLink hub with an internet connection. If you do not have one, compare starter kits that include a hub; if you already do, check the sensor or valve product page for its exact hub requirement and box contents.
Will a leak sensor shut off my water by itself?
No. A sensor detects water and can send supported alerts through a connected hub. Automatic shutoff also needs a compatible valve controller or operator and a configured sensor-to-valve action. Check the selected products for compatibility and what is included.
How do I choose silent or audible leak alerts?
Water Leak Sensor 1 (YS7903) is silent; Water Leak Sensor 4 (YS7906) has a built-in sounder. For alerts elsewhere in the home, use a SpeakerHub or compatible siren with the alert action configured. Test audibility from the rooms that matter to you, and check the exact model’s sound and silencing controls before buying.
Which leak-sensor style should I choose?
The right style depends on where water is likely to appear and how much area must be covered. Puck, probe, and rope-style sensors serve different placement needs. Compare sensor styles →
How do I know whether a valve operator will fit?
Check your existing valve type and size, plus the space and orientation around its handle. Review the selected operator’s dimensions and compatibility information before purchase. If the fit is uncertain, contact support with photos of the valve and installation area. Compare shutoff options →
What works if my power or internet goes out?
Battery-powered local alarms, directly paired shutoff and remote alerts have different requirements.
What you want to happenInternet connection lostHousehold power lost
Hear the sensor’s own alarmOn models with a built-in sounder
Can continue on the sensor’s working batteries.
Can continue on the sensor’s working batteries.
Close a directly paired valveCompatible sensor + Valve Controller 2/EVO example
Can continue after Control-D2D pairing, while both devices have power and remain in radio range.
Requires working batteries or suitable backup power for both paired devices.
Get app, email or SMS alertsThrough a standard Hub or SpeakerHub
Requires an internet connection. A local valve action does not restore remote notifications.
Requires the hub, router and internet connection to remain powered and online.