
Continuous temperature recording on the flow, on the recirculation return and on two storage tanks, at the top and at the bottom, with an alarm below the thresholds of your monitoring plan and an exportable history for the logbook. PT100 probes, battery-powered sensors, LoRaWAN radio transmission.
What it does
- Two sensors with a PT100 probe measure the water temperature on the flow and on the return of the recirculation loop: the return is the coldest point of the network and the one the monitoring plan asks you to keep under observation.
- On each storage tank a two-channel sensor reads one probe in the upper part and one in the lower part. The display shows the two temperatures to anyone passing through the plant room, without a phone.
- The thresholds are set according to your plan: the usual reference values are 60 °C in the storage tank and 50 °C on the recirculation return. Below the threshold the notification is sent to your smartphone.
- The history also records the thermal shock and thermal disinfection cycles: the temperature reached and the duration stay documented.
- The temperature and humidity sensor follows the boiler room; the floor water sensor reports leaks from tanks, pumps and safety valves, with a buzzer on site and a notification.
- Charts and history can be consulted from smartphone and PC and exported, so you can attach them to the monitoring logbook instead of taking manual readings in the plant room.

How it is installed
What is in the kit

| Qty | Device | What it is for |
|---|---|---|
| 1 | Compact indoor LoRaWAN gateway | Collects the sensor data and forwards it to the platform. Ethernet or Wi-Fi, USB-C 5 V power supply. |
| 2 | Temperature sensor with PT100 probe, from -50 to +200 °C, IP67 | Water temperature on the flow and on the recirculation return. Accuracy ±0.6 °C. |
| 2 | Two-channel temperature sensor with display, IP65 | Reads two probes per storage tank, top and bottom. Internal memory of 10,000 readings. |
| 4 | PT100 probe for the two-channel sensor | Two for each storage tank, in a thermowell. Cable from 1.5 to 2 m. |
| 1 | Temperature and humidity sensor, IP67 | Conditions of the boiler room. |
| 1 | Floor water sensor with buzzer, IP67 | Leaks from tanks, pumps and safety valves. |
Milesight devices of the highest quality with the manufacturer's warranty. Batteries included in all the sensors; the sensors with display can also be powered at 5 V via USB-C; the gateway is mains-powered.
Available sizes
The size is selected at the top, together with the version and the connectivity. The diagram, the photo and the table above show the “1 recirculation loop” size; with the other sizes only the quantities of the devices listed below change, the rest of the kit is identical.
- 1 recirculation loop: 2 PT100 temperature sensors
- 2 recirculation loops: 4 PT100 temperature sensors
- 3 recirculation loops: 6 PT100 temperature sensors
In the complete kit the installation material linked to these devices (brackets, thermowells, clips, cables, boxes) follows the size selected. For a different size, write to us from the contacts section.
Available connectivity options
- Customer network (Ethernet/Wi-Fi): 1 compact indoor LoRaWAN gateway
- Built-in 4G: 1 compact LoRaWAN gateway with 4G. SIM not included
- Large building (IP65 gateway, PoE): 1 semi-industrial LoRaWAN gateway
In the complete kit the material for the gateway (network cable, pole, PoE injector) changes accordingly. The SIM for the 4G versions is not included.
Choose the version
- The Milesight devices in the table
- Installation guide and initial configuration
- For those who already have free thermowells on the pipework and the storage tanks
- Everything in the basic version
- 6 half-inch thermowells, 100 mm long, for the probes on the flow, the recirculation and the storage tanks
- Clamps for fixing the probes in contact and stainless steel clamps for the transmitter bodies on pipes
- Ethernet cable for the gateway
- Wall plugs, screws, double-sided tape, numbered labels and installation diagram
Before you order
Is an internet connection needed in the plant room?
It is needed at the point where the gateway is installed, and the gateway can sit outside the plant room: a network socket or the Wi-Fi coverage of the building. The sensors do not use Wi-Fi, they talk to the gateway by radio. If there is no line, the version with a 4G gateway is available, which requires a data SIM (not included, any operator, traffic below 1 GB per month) and a spot where the cellular signal arrives. It is selected when ordering.
Does it replace the manual readings of the legionella logbook?
For the plant room points, yes: flow, recirculation return and storage tanks are recorded every 10 minutes, day and night, with date and time, and the history is exported so it can be attached to the logbook. What stays outside are the points the kit does not measure: the distant outlets, that is taps and showers, where checking the delivery temperature remains manual, and the microbiological sampling. Thresholds and frequencies are those of your risk assessment document: the kit applies them, it does not set them.
Is a plumber or an electrician needed?
An electrician, no: the sensors are battery-powered and the gateway runs on 5 V. A plumber is only needed if the thermowells are missing: screwing a thermowell into a free socket is a short job, but the section has to be isolated and drained. Many cylinders already have free pockets for a thermometer and probes, and in that case it is enough to slide the probe in. Without a thermowell the probe is mounted in contact under the insulation, with a less faithful reading.
How accurate are the probes and do they cope with thermal shock?
The sensors on the flow and the recirculation have a PT100 probe with an accuracy of ±0.6 °C and a range from -50 to +200 °C. The standard PT100 probes of the two-channel sensors work from -40 to +125 °C, with an accuracy of ±0.5 °C up to 40 °C and ±1 °C beyond. The cycles at 70-80 °C are therefore within the measuring range of all the probes and stay recorded. The two-channel sensor complies with EN 12830.
The plant room is in the basement: does the signal get through?
It depends on the walls and floors between the sensors and the gateway: that is why the gateway goes as close as possible to the plant room, even in the room next door. In most buildings the compact gateway is enough. For large buildings, thick walls, several blocks or a plant room far from the network point there is the “large building” version, with a semi-industrial IP65 gateway of greater range, which can be powered via PoE and can also sit inside the plant room. One gateway handles hundreds of devices: the same one also serves other kits in the building.
I have more recirculation loops or more storage tanks
Among the product options you will find the sizes with 2 and 3 recirculation loops: each additional loop adds two sensors with a PT100 probe, flow and return. For more storage tanks one two-probe sensor is added for each of them; the gateway and the platform stay the same. For sub-stations, heat exchangers or several plant rooms, write to us from the contacts section with the system layout: we will send you the composition and the quotation of the adapted kit.
Battery life
Sensors on the flow and the recirculation: 19,000 mAh lithium battery, declared life of 10 years with one reading every 10 minutes at 25 °C. Two-probe sensors with display: more than 2.7 years on batteries, with no limit if powered via USB-C. Boiler room sensor: up to 10 years. Water sensor: about 5.7 years with a button cell. All the batteries are replaceable and the charge level is visible in the app.
Where is the data viewed and are there any fees?
On the manufacturer's app and portal, from smartphone and PC, with charts, thresholds and notifications; no fee for basic use. If there is a building management system or a maintenance software, the gateway can also send the data to that system (MQTT or HTTP): the configuration is included.
What happens if the internet goes down?
The sensors keep measuring and hold the readings in their internal memory: 1,000 readings for the sensors on the flow and the recirculation, 10,000 for those on the storage tanks. When the line is restored they retransmit them and the history is completed. Notifications on your smartphone do not go out until the line is back; the display of the sensors on the tanks and the buzzer of the water sensor work in any case.
Do they cope with the heat and humidity of the plant room?
The sensors with a probe on the flow and the recirculation, the room sensor and the water sensor are IP67; the two-channel sensor with display is IP65 and works from -30 to +70 °C. The water sensor works from -10 to +60 °C. The compact gateway is an indoor device, IP30, from -20 to +50 °C: it goes in a dry room, or you choose the version with the IP65 gateway.
What is not included
- Storage tanks, boiler, pumps, mixing valve and pipework: these are the ones in your system
- The sockets on the system and the plumber's work to fit the thermowells
- The data SIM, in the version with a 4G gateway, and the USB power adapter of the compact gateway
- Checking the temperatures at the outlets and the microbiological analyses
- In the "devices only" version: thermowells, clamps, network cable and small fittings
Shipping
Shipping: free to Italy and throughout the EU. Delivery in 10-20 working days.