Ajax LeaksProtect: The UK Installer's Guide to Water Leak Detection
Most UK alarm customers will never be burgled. A lot of them will be flooded. This guide is for installers who want to add Ajax LeaksProtect water leak detection to systems they are already fitting — where the detectors actually go, how many a property needs, how to drive a motorised valve from an Ajax Relay so the water shuts itself off, and how to bring existing wired leak sensors onto the same hub. Every figure below comes from Ajax Systems' published specifications and is cited inline.
What this guide covers
- The device: LeaksProtect Jeweller is a battery wireless flood detector with contact pairs on all four sides and a detection time within 0.15 s.
- The placement rule: on the floor, at the lowest point, under the appliance — not beside it and never on a plinth.
- The shut-off: LeaksProtect triggers an Ajax Relay, the Relay drives a motorised or solenoid valve, and the supply closes without anyone being home.
- The retrofit path: existing wired leak or flow sensors come onto the hub through a Transmitter or a MultiTransmitter — up to 18 wired zones on one radio link.
- The commercial case: escape of water is the single biggest cause of UK home insurance claims, so this is a five-minute add-on that sells itself.
What is Ajax LeaksProtect and what does it detect?
LeaksProtect Jeweller is a wireless flood detector that raises an alarm the moment water bridges a pair of contacts on its underside. Contact pairs sit on all four sides of the enclosure, so the detector responds whichever direction the water arrives from, and it reports the alarm to the hub within 0.15 s (LeaksProtect Jeweller technical specifications). It is always active — unlike an intruder detector, it does not care whether the system is armed, disarmed or in night mode.
It also tells you when the water has gone. Ajax notify both the start and the end of a flooding event, which matters on a monitored commercial site where someone has to decide whether to send an engineer out at 2 a.m. or wait for the morning. We stock the detector in both finishes: the Ajax LeaksProtect Flood Detector in white and the Ajax LeaksProtect Flood Detector in black, both on the Jeweller radio protocol, both same-day dispatch from Leicester.
Why escape of water is worth putting on every Ajax quote
Escape of water is the most common home insurance claim in the UK, and it is getting more expensive. Analysis of UK home insurance claims put escape of water at almost one in three of all claims declared (GoCompare), and the Association of British Insurers reported that UK property insurers paid out a record £6.1 billion in 2025, including £1.2 billion of weather-related property claims covering burst and frozen pipes as well as storms and flooding — a 14% rise on the previous year (ABI, February 2026).
For an installer, that translates into a simple conversation. A pair of LeaksProtect detectors under the kitchen sink and behind the washing machine costs less than a single motion detector, adds five minutes to the commissioning visit, and protects against the failure mode the customer is statistically most likely to suffer. On lettings, holiday lets, empty commercial units and listed buildings, it is the part of the quote that gets signed first.
LeaksProtect Jeweller specifications at a glance
| Specification | LeaksProtect Jeweller |
|---|---|
| Detection method | Contact pairs on all four sides |
| Detection time | Within 0.15 s |
| Radio protocol | Jeweller, two-way, encrypted, frequency hopping |
| Frequency bands (UK/EU) | 866.0–866.5 / 868.0–868.6 / 868.7–869.2 MHz |
| Modulation / max ERP | GFSK / up to 20 mW |
| Radio range (open space) | Up to 1,300 m to a hub or range extender |
| Communication loss detection | From 36 s (default polling settings) |
| Power | 2 × AAA pre-installed, up to 5 years calculated life |
| Enclosure height | 14 mm (about 62 × 62 mm footprint) |
| Protection class | IP65, indoor use only |
| Operating temperature | 0 °C to +50 °C, humidity up to 100% |
| Warranty | 24 months |
All figures above are taken from the official LeaksProtect Jeweller technical specifications. Note the IP65 rating is dust and jet-resistance for splashes, not an invitation to fit it outdoors — Ajax state the device is for indoor use only.
Where should you place LeaksProtect in a UK property?
Place the detector flat on the floor at the lowest point water will reach, directly under or behind the appliance or pipework you are protecting. Water finds the floor before it finds anything else, and a detector on a plinth, on top of a cabinet base, or sat on a bath panel will simply be missed. The 14 mm height is the whole point of the design: it slides under a washing machine or a dishwasher where the leak actually starts.
| Location | Where exactly | Why |
|---|---|---|
| Kitchen | Under the sink unit, at the back | Trap, isolation valves and flexi hoses all fail here first |
| Utility | Under the washing machine or dishwasher | Burst fill hose is the classic overnight claim |
| Bathroom / en-suite | Beside the bath panel and behind the WC pan | Slow overflow and failed pan connectors soak the ceiling below |
| Airing cupboard / plant room | Floor under the cylinder or manifold | Unvented cylinder and underfloor manifold leaks run for days unseen |
| Loft | Under the cold water tank, in the tray | A tank overflow does the most damage of any domestic leak |
| Commercial | Riser cupboards, server room, under AC condensate trays | Water above IT kit is a business-continuity event, not a mop-up |
Two placement mistakes to avoid: do not site a detector where a routine mop or a pet bowl will wet it (you will teach the customer to ignore alarms), and do not put it anywhere it can be kicked out of position when the appliance is pulled out for servicing.
How many LeaksProtect detectors does a property need?
Count the wet points, not the rooms. Every independent source of water gets its own detector, because a detector two metres away in the same room will only alarm once the floor is already covered.
| Property | Typical count | Recommended build |
|---|---|---|
| 1–2 bed flat | 2–3 detectors | Kitchen sink, washing machine, bathroom — detect and notify only |
| 3–4 bed house | 4–6 detectors | Add utility, en-suite and airing cupboard; add a Relay and valve on the rising main |
| Holiday let / second home | 4–6 detectors | Automatic shut-off is mandatory — nobody is there to hear the siren |
| Small commercial unit | 6–12 detectors | Riser, WCs, kitchen, server room, plus wired flow sensors via MultiTransmitter |
Because LeaksProtect runs on the same Jeweller radio as the rest of the system, the detectors simply consume device slots on the hub you have already specified. If you are building the system from scratch, the Ajax system builder lets you add them alongside the intruder devices in one order.
Which Ajax hub do you need for water leak detection?
Any current Ajax hub will run LeaksProtect — the choice is driven by device count and communication channels, not by the leak detectors. For a straightforward domestic install the Ajax Hub 2 (2G) Jeweller is enough. Where the customer wants photo verification alongside leak detection, or the device count is heading past 100, step up to the Ajax Hub 2 Plus Jeweller, which adds Wi-Fi and LTE alongside Ethernet.
On sites with no fixed line — holiday lets, agricultural buildings, vacant units — the Ajax Hub 2 (4G) Jeweller keeps the alarm path up on cellular alone, which is exactly the scenario where an unattended leak does the most damage. We also hold clearance stock of the Ajax Hub (4G) Jeweller control panel for budget retrofits. Whichever hub you choose, fit the matching Ajax 12 V power supply adapter and, on Hub 2 Plus and Hub 2 (4G), keep a spare Ajax hub backup battery in the van — a hub that has been offline since the last power cut will not tell anyone about the leak.
If the job is a first-time Ajax system rather than an add-on, the pre-built Ajax Hub 2 Kit 1 and Ajax Hub 2 Kit 3 give you hub, detectors, keypad or fobs and both sirens in a single box, and you add the leak detectors on top. Our Ajax StarterKit guide covers when a kit beats a bill of materials.
How do you make the water shut off automatically?
Pair a LeaksProtect alarm to an Ajax dry contact Relay in an automation scenario, and wire the Relay to a motorised or solenoid valve on the rising main. When the detector goes into alarm, the hub fires the scenario, the Relay changes state, and the valve closes — whether or not anyone is in the building or looking at their phone. Ajax publish this as a standard flood-prevention scenario for the Relay (Ajax Relay product page), and the step-by-step wiring is in their support article on controlling water supply via Ajax.
The Relay itself is a 39 × 33 × 18 mm module with a dry contact output, powered from 7–24 V DC, with bistable and pulse modes (pulse configurable from 1 to 255 seconds). Because the dry contact is not galvanically connected to the device power supply, it can switch a low-voltage valve circuit independently of the Relay's own supply, and it will sit happily in a junction box, a consumer unit enclosure or on DIN rail next to the incoming main.
Three practical points for UK installs. First, specify the valve deliberately: a latching motorised ball valve holds its last position on power loss, while a solenoid valve typically needs to be held open, so a power cut closes the water — acceptable in a holiday let, a nuisance in an occupied house. Second, power the valve from a supply with battery backup, or the shut-off fails in exactly the storm that caused the leak. Third, put the valve after the stop tap and leave the manual stop tap accessible — you are adding automation, not removing the plumber's isolation point.
A note on Ajax WaterStop: Ajax do produce their own Jeweller shut-off valve, and it is the neatest answer where it suits the pipework. We do not currently hold it in stock, so the builds in this guide use the Relay plus a third-party valve, which is also the cheaper and more flexible route on 22 mm and 28 mm mains.
How do you bring existing wired leak sensors onto an Ajax hub?
Use a Transmitter for one wired device and a MultiTransmitter for many. The Ajax Universal Transmitter is a single-channel module that takes a third-party wired detector's alarm and tamper contacts and reports them to the hub over Jeweller, supporting NC and NO contact types and providing a 3.3 V output for the connected device (Ajax Transmitter). It is the right answer for one legacy flood probe under a cylinder or a single flow switch on a plant room main.
Where a commercial site already has a wired leak-detection loop, water flow sensors or tape-style leak cable, the Ajax MultiTransmitter Jeweller in white (or the black MultiTransmitter) brings up to 18 wired third-party detectors onto the hub over a single radio link (Ajax MultiTransmitter). One module, one radio path to survey, eighteen zones reported individually in the app. Our Ajax MultiTransmitter installer guide covers zone wiring, resistors and power budgeting in detail.
What about range in basements and plant rooms?
Leak detectors live in the worst radio locations in the building: under metal appliances, inside cupboards, in basements, behind cylinders. LeaksProtect is rated at up to 1,300 m to a hub or range extender in open space, but a detector sitting on a concrete floor under a steel washing machine in a basement utility is a long way from open space.
Survey each position with the Jeweller signal strength test before you leave the device there, and accept three bars, not two. If a basement or detached plant room will not hold a link, add an Ajax ReX 2 Jeweller range extender on mains power at the top of the stairs rather than moving the detector somewhere it will not see water. Our complete Ajax wireless alarm system guide covers hub siting and radio survey technique across a whole install.
How should a leak alarm actually alert the customer?
Push notification alone is not enough for water. Add an Ajax HomeSiren U Jeweller indoors so an occupied property gets an audible warning while the leak is still a puddle, and configure the leak alarm as a separate scenario from the intruder siren so the customer can tell the difference from the next room. On unoccupied properties the audible is irrelevant — what matters is the app push and, where the system is monitored, the signal to the ARC.
Do not put the leak alarm on the Ajax StreetSiren DoubleDeck. An external sounder screaming at 3 a.m. because a washing machine hose has split is a neighbour complaint, not a security response. Keep water on the indoor sounder and the app.
While you are in the app, this is the natural moment to add life-safety cover on the same hub. The Ajax FireProtect 2 RB (Heat/Smoke/CO) and the mains-free Ajax FireProtect 2 SB put smoke, heat and carbon monoxide detection on the same panel and the same app as the leak detectors — one system, one set of notifications, one maintenance visit.
LeaksProtect commissioning checklist
- Add the detector to the hub by QR code, and name it by location, not by number — "Kitchen sink" beats "LeaksProtect 3" at 2 a.m.
- Run the Jeweller signal strength test with the detector in its final position, on the floor, with the appliance pushed back in.
- Test with water, not with a wet finger: a splash across two contacts on the same side is the honest test.
- Confirm the alarm reaches the app, the indoor siren and, if monitored, the ARC.
- If a Relay and valve are fitted, trigger a real alarm and watch the valve close, then confirm the customer knows how to reopen it.
- Check the recovery notification arrives when the detector dries — that is the message that saves an unnecessary call-out.
- Record battery state at handover and set the customer's expectation: up to five years, and the app will warn long before it fails.
Five mistakes installers make with leak detection
The five that generate call-backs, in order of frequency:
- One detector per room instead of one per wet point. The sink leak does not reach the detector by the bath until the floor is ruined.
- Mounting it off the floor. A detector on a plinth or a shelf detects nothing until the flood is ankle-deep.
- Fitting shut-off with no backup power on the valve. Storm, power cut, burst pipe — all three arrive together.
- Putting leak alarms on the external siren. One 3 a.m. false activation and the customer disables the whole scenario.
- Skipping the radio survey because "it is only a leak detector". It is in the worst radio position in the building; survey it like a detector that matters.
Frequently asked questions
Does Ajax LeaksProtect work when the alarm system is disarmed?
Yes. LeaksProtect is always active and reports flooding 24/7 regardless of the security mode, the same as Ajax fire detectors.
How long do LeaksProtect batteries last?
Up to five years on the two pre-installed AAA cells, with low-battery warnings in the Ajax app well before the end of life.
Can LeaksProtect turn the water off on its own?
Not by itself. It needs an automation scenario and an Ajax Relay driving a motorised or solenoid valve, or an Ajax WaterStop valve, to physically close the supply.
Can I fit LeaksProtect outdoors or in a wet room?
No. It carries an IP65 rating but Ajax specify indoor use only, and permanent standing water or wash-down areas will cause nuisance alarms.
How many LeaksProtect detectors can one hub handle?
They use standard Jeweller device slots, so the ceiling is the hub's overall device limit rather than a separate leak-detector limit — 100 devices on a Hub 2, 200 on a Hub 2 Plus.
Can I connect an existing wired leak sensor to Ajax?
Yes. A Transmitter handles one wired detector; a MultiTransmitter brings up to 18 wired third-party detectors onto the hub over a single Jeweller link.
Related guides
- Ajax Wireless Alarm Systems: The Complete UK Installer Guide
- Ajax MultiTransmitter Installer Guide
- Ajax Keypad Comparison: KeyPad, Plus, TouchScreen & Outdoor
- Ajax Fire Hub Jeweller EN54: UK Installer Guide
- Ajax DoorBell: The UK Installer's Guide
Order Ajax LeaksProtect and flood-prevention parts from Netview
Netview is an authorised UK Ajax stockist based in Leicester. LeaksProtect in white and black, the dry contact Relay, Transmitter and MultiTransmitter modules, and the full Hub 2 range are held in stock for same-day dispatch, with trade pricing for installers. Build a system to your survey with the Ajax system builder, or browse the full range at netviewcctv.co.uk.
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