Question 1

What is HydroNode and who is it for?

Accepted Answer

HydroNode is a free platform for environmental sensors over WiFi and LoRaWAN. Your device sends readings, HydroNode stores them, draws the charts, learns what is normal and tells you when something is off. It is built for growers, researchers, facility managers, weather station operators and hobbyists who want to track temperature, humidity, CO₂, soil moisture, pH or water quality without running their own server.

Question 2

What sensor types are supported?

Accepted Answer

More than 30 measurement types for air, climate, soil, water, weather, device and power data, such as TEMPERATURE, HUMIDITY, CO2, PM2_5, SOIL_MOISTURE and WATER_PH. Keys are case-sensitive. The full list with units is at https://hydronode.tech/docs/guide/sensor-types/.

Question 3

Is HydroNode free?

Accepted Answer

Yes. Every account can create up to 20 sensors with every feature included. There is no subscription, no card and nothing to buy. Press Create sensor on the Dashboard; the form shows how many of your 20 sensors are used. If our running costs grow, we may introduce a small fee for new sensors in the future and will announce it in advance.

Question 4

I still have an activation code. Do I need it?

Accepted Answer

No. Activation codes are a leftover from when sensor slots were sold. Creating a sensor needs no code any more. For questions about an earlier purchase, write to support@hydronode.tech.

Question 5

Where do I find what in the app?

Accepted Answer

After you sign in, the top navigation holds Dashboard, Stations, Anomalies, Operations, Docs and Blog. The Dashboard is your home page with every device, its live values, firmware and battery. Click a device name for its sensor page, then Settings at the top right for everything you can change. Stations shows the map, Anomalies the Incident Feed across all sensors, Operations your automations, calibration, reports and export. Profile, under your name at the top right, holds the LoRaWAN webhook, API tokens and Downlinks.

Question 6

What is the difference between a sensor and a station?

Accepted Answer

A sensor is the private identity of your device. It receives and stores the readings. A station is an optional extra for a physical outdoor installation, such as a garden, a rooftop or a weather station. It adds a location and, if you like, a place on the public map. Direct and LoRaWAN connections can both be stations. The sensor must be saved as Outdoor first; indoor sensors cannot become stations.

Question 7

How do I connect my LoRaWAN sensor?

Accepted Answer

Create a sensor with Outdoor as the environment. Register the device and its keys with The Things Network, ChirpStack or Helium; HydroNode never needs your AppKey or session keys. On the sensor page open Settings → Connection and, under LoRaWAN, enter the 16 character DevEUI and the Application ID (TTN: the application ID, ChirpStack: the application UUID), then press Link device. HydroNode shows the Webhook address. Add it as an uplink webhook on your network server, then describe your payload under Payload formats (fPort).

Question 8

What LoRaWAN networks are supported?

Accepted Answer

The Things Network v3, ChirpStack v3 and v4, and Helium through its ChirpStack compatible format. All of them send uplinks to the same private HTTPS webhook address. Downlinks, for commands and new settings, work with The Things Network and ChirpStack once you connect them in Profile → Downlinks.

Question 9

How do I make a sensor a station?

Accepted Answer

On the sensor page open Settings → General. Set Environment to Outdoor and save. Then turn on Use as a station in the Station group of the same section. This works for Arduino, ESPHome, Device Builder and LoRaWAN devices alike; the Sensor ID, Secret and every reading stay as they are. A LoRaWAN device becomes a station automatically when you link it.

Question 10

How do I put a station on the public map?

Accepted Answer

In Settings → General of the sensor, press Location and public map. That opens the station settings. Set the location, either by hand or with Use this device's location, then turn on Show on the public map. The station appears under Stations for everyone. Turn the switch off again and it is private.

Question 11

What happens if I remove the location or stop using a sensor as a station?

Accepted Answer

Remove location in the station settings deletes the coordinates and takes the station off the public map. The station, the sensor and every reading stay. Switching Use as a station off removes the location and the place on the map as well, but keeps the sensor, its shares and every reading. To erase readings for good, delete the sensor under Settings → Transfer or delete.

Question 12

Where are Fleet and the sensor list now?

Accepted Answer

Both are part of the Dashboard. Its device list shows every device with live values, state, firmware and battery. The gear (⚙) at the end of a row opens the device drawer with updates over the air, config changes and problems. Device builder, Templates, Job history and Bulk change sit in the head of the device list. Old links to /fleet and /sensors lead to the Dashboard.

Question 13

Which devices update over the air?

Accepted Answer

Boards flashed with the Device Builder through Flash now, with HydroNode firmware 0.5.0 or later. ESP32, ESP32-S2, S3, C3 and C6 take new firmware and new config. The ESP8266 takes new config only, because it has no room for a second copy of the firmware. Your own sketches, ESPHome devices and LoRaWAN sensors show no OTA in the Firmware column: the Dashboard shows their health, but HydroNode does not update them.

Question 14

How do I update one device?

Accepted Answer

On the Dashboard, click the gear (⚙) on the device row. In the drawer, Update to 0.8.0 installs the newest signed firmware. Change config opens the Device Builder with the saved setup; go through wiring, power and timing and press Send. When a button is not possible, it says why, for example Config only on an ESP8266 or Needs USB reflash on old firmware.

Question 15

Do I still need a USB cable?

Accepted Answer

Once. Flash the board with the Device Builder (Flash now). From then on, new firmware, the send interval, the power mode or an extra value reach it over WiFi. A board with firmware before 0.5.0 shows Needs USB reflash in its drawer: reflash it one last time with Reflash via USB, or with Reflash under Settings → Device setup. New firmware for an ESP8266 always needs USB.

Question 16

What happens if an update fails?

Accepted Answer

The board goes back to what it ran before, by itself. After an update it restarts and checks itself in its first wake cycle: up to three tries in at most two minutes. Until it passes, the old firmware and config stay on the board. If the check fails or the board restarts early, it rolls back and reports why, for example sensor_read_failed:bme280. The Dashboard shows Rolled back with the reason, and you get a push notification.

Question 17

What is the difference between Strict and Lenient?

Accepted Answer

Both decide when an update counts as good. Strict, the default, waits for a signed reading accepted by HydroNode and a successful read of every configured sensor. Lenient only waits for the accepted reading; use it for a device whose sensor is already broken and would fail Strict every time. Set your account default with the gear in Job history (Default verify mode), override it per device under Verify mode in the device drawer, or choose it for one change in the bulk change dialog.

Question 18

Can I stop an update?

Accepted Answer

Yes, while it is Queued, Offered or Waiting for check-in. Press Cancel next to the state in the device drawer. The board keeps its current firmware and config, because nothing was downloaded yet. Once the download or the config change started, the job runs to its end; a failed check still rolls back on its own.

Question 19

How do I change many devices at once?

Accepted Answer

Press Bulk change in the head of the device list, or tick the devices you want. The bar at the bottom starts the change dialog. Change picks what to change, Devices picks the boards (All with update available takes every board with new firmware waiting), and Check & review runs every rule for every device and sorts them into OK, Warning and Not possible. Nothing goes out before you press Create jobs.

Question 20

Why do I have to confirm twice for some devices?

Accepted Answer

A device below 30 % battery needs a second confirmation. A firmware download is the most power hungry thing a board does. If the battery dies halfway, the old firmware starts again, but the board may stay quiet until it is charged. The first click on Create jobs names the weak devices, the second one creates the jobs.

Question 21

What is a template?

Accepted Answer

A saved Device Builder setup without a sensor and without WiFi: board, wiring, power and timing. Open Templates in the head of the Dashboard device list. Flash every board of the same kind from one in four steps, and change all of them later in one go. Templates have versions; after you save a new one, Apply to linked devices… checks each linked board and updates it over the air. You can keep up to 50 templates.

Question 22

What does the Device Builder save on my sensor?

Accepted Answer

After a flash or download it saves its answers as the device setup of the sensor: board, wiring, power and timing, plus the firmware version and a config revision. It never saves the WiFi network, the WiFi password, the sensor Secret or any code. The setup makes one click reflashing and config changes over the air possible. See it, save it as a template, reflash or forget it under Settings → Device setup.

Question 23

What do the battery thresholds on the device do?

Accepted Answer

A device on a battery sends half as often below Save, turns its radio and outputs off below Radio off, sleeps an hour at a time below Standby and runs normally again from Resume on. Change them on the sensor page under Settings → Pressure and battery, in the On the device box, and press Send to device. Green means the device runs these values, yellow that it has not taken them yet. HydroNode firmware 0.8.0, your own sketches with HydroNode Library 1.8.0 and HydroNode stations with firmware 2.1 take new values; ESPHome only reports them.

Question 24

How do new values reach a LoRaWAN station?

Accepted Answer

As a downlink through your network server. Open Profile → Downlinks once, pick ChirpStack or The Things Network, then 1 Connect, 2 Test and 3 Turn on. After that the station takes new values after its next uplink and confirms them.

Question 25

Can HydroNode read my WiFi password?

Accepted Answer

No. By default the password goes from the page straight onto the board or into your download and is gone when you leave the page. If you choose Save this network with your passkey, your browser encrypts the network with a key that comes from your passkey before anything is sent. HydroNode stores only that encrypted copy and cannot read the network name or the password. Config changes over the air never contain WiFi; the board keeps its own.

Question 26

How do I save my WiFi with a passkey?

Accepted Answer

On the WiFi step of the Device Builder, type the network, then choose Save this network with your passkey and confirm. The first time, your browser creates a passkey named "HydroNode WiFi vault". Next time, on this or any other computer where the same passkey is available (iCloud Keychain, Google Password Manager, 1Password, a security key, or your phone by QR code), choose Fill in with your passkey. The option only appears in browsers that can encrypt with a passkey. Use it only on a computer that is yours: anyone who can unlock it can use the passkey.

Question 27

How long are saved WiFi networks kept?

Accepted Answer

Thirty days after you last filled in or saved them. Every use starts the 30 days again. You can keep up to 10 networks. Remove one with its bin icon, or all of them with Delete saved networks, for example when the passkey is lost: without it they cannot be opened, not even by HydroNode. Boards that already use a network keep working. Deleting your account deletes the saved networks too.

Question 28

Who is told when an update is done?

Accepted Answer

The person who started the change gets one push notification when all its devices are done, for example "3 of 3 devices installed firmware 0.8.0", and right away if a device rolls back. It needs a current version of the iOS or Android app. Job history in the head of the Dashboard device list shows every change and its outcome for 30 days.

Question 29

How does anomaly detection work?

Accepted Answer

Every reading is checked the moment it arrives: against the limits you set, against published guidelines such as WHO or UBA values, and against a band HydroNode learns for each measurement from the last 28 days, including its daily pattern. Findings that belong together become one incident. You see them in the Anomalies panel on the sensor page and in the Incident Feed under Anomalies. A value that is only unusual reaches Warning at most; only a broken limit or guideline can make an incident critical.

Question 30

Why does my new sensor not show any anomalies yet?

Accepted Answer

The learned band needs at least 20 readings spread over 6 hours. The daily pattern needs 3 days and is fully trusted after 7. Until then HydroNode only checks your own limits and published guidelines, which work from the first reading.

Question 31

I get too many anomalies. What can I do?

Accepted Answer

On the sensor page press Settings. Under Anomaly detection, pick a calmer Sensitivity such as Relaxed. Under Limits and targets, choose Use my own range and set Ideal from and up to, so HydroNode knows which range is fine for you. In the Incident Feed, give expected incidents the verdict Normal. If only the messages bother you, set Notifications to Important only: purely statistical anomalies then stay in the app.

Question 32

What do Normal, Issue and Fault mean in the Incident Feed?

Accepted Answer

They are your verdict on an incident. Open it under Anomalies and pick one under Your verdict. Normal says the value was expected, Issue confirms a real problem, Fault marks a sensor or measuring error. Rated incidents count under Reviewed at the top of the feed.

Question 33

What does the AI analysis do?

Accepted Answer

It writes a short explanation of how the sensor is doing: a summary, up to 6 findings, up to 3 recommendations and what it could not judge. HydroNode calculates scores, severities and incidents first; the AI only explains that result and may not contradict it. Detection and alerts never depend on the AI.

Question 34

When does a new AI analysis run?

Accepted Answer

Automatically every 6 hours if the sensor sent new readings, right after an important incident opens, or when the owner presses Analyze in the Anomalies panel of the sensor page (up to 6 per day per account). A sensor is analysed at most once every 30 minutes. If nothing changed since the last analysis, you get that one back instead of a new one.

Question 35

What data does the AI see?

Accepted Answer

The analysis runs on Amazon Bedrock in Frankfurt (EU). It receives recent readings and averages, learned bands, open incidents, applicable guidelines, the environment and the time zone. It does not receive your name, email address, sensor name, channel names, notes or location. Your data is not used to train models.

Question 36

What is the air quality score?

Accepted Answer

A score from 0 to 100 for sensors that measure at least one air pollutant, such as CO₂ or particulate matter. Each pollutant is scored against published guidelines, and the most important groups weigh more. The score can be at most 20 points better than the worst group, so good values cannot hide one bad pollutant. A station shows the score of its worst sensor.

Question 37

What happens if my sensor goes offline?

Accepted Answer

HydroNode learns how often the sensor reports. After 3× that interval without a reading (at least 5 minutes) it is Delayed, after 12× (at least 15 minutes) Offline. By default you get a push when it goes offline and when it is back. Change the stages and channels on the sensor page under Settings → Monitoring. For a rule across several sensors, use Operations → Automations → New automation with the trigger The sensor goes quiet. History and settings stay untouched while the device is offline.

Question 38

What is Low battery standby?

Accepted Answer

A battery device that drops below its Radio off threshold sends one last round and then goes quiet on purpose to save the battery. HydroNode shows Low battery standby instead of Offline, and widgets do not treat the old value as a fault. You get a message through the Low battery standby channel under Settings → Monitoring, a push by default, and another one when the device is back.

Question 39

How do I choose which alerts I get?

Accepted Answer

Per sensor, on the sensor page under Settings → Notifications. Off sends nothing for that sensor, not even critical alerts. Important only, the default, sends warnings that need you, incidents that get worse and critical alerts. Everything also sends updates, recoveries and new AI summaries. Offline alerts are set separately under Settings → Monitoring.

Question 40

Why did I not get a push for an anomaly I see in the app?

Accepted Answer

An anomaly that is only statistically unusual is informational and is only sent with Everything. HydroNode also waits at least 30 minutes between two alerts about the same incident, unless it gets worse, and never alerts on a jump the next reading does not confirm. Also check that Notifications is not set to Off and that the app is allowed to send notifications.

Question 41

What happens to iOS notifications when I sign out?

Accepted Answer

Signing out unregisters that iPhone or iPad from your HydroNode account, so it no longer receives account specific notifications. Signing in again and granting notification permission registers it again. You can also review registered devices in the app.

Question 42

What is the device console?

Accepted Answer

A developer console docked at the bottom of the sensor page. It shows every request your device sends, including refused ones with the reason, and has tabs to decode LoRaWAN payloads, check link quality or timing, send commands and build payloads. Press ` to open or close it. The Dashboard has the same dock for all your devices at once. The owner and people with a Can manage share can open it.

Question 43

Why are my requests rejected?

Accepted Answer

Open the console and pick the Rejected filter in the Live tab. For HTTP, 401 Invalid signature means the signed string does not match; the line shows the exact string the server expected. 401 Invalid timestamp means the device clock is more than 2 minutes off; the Timing tab shows by how much. For LoRaWAN, the most common reason is an uplink on an fPort without a layout; add it under Settings → Connection → Payload formats (fPort).

Question 44

Can I test a LoRaWAN payload without a device?

Accepted Answer

Yes. Paste hex, Base64 or decimal bytes into the Decoder tab of the console, or into Test a payload next to your fPort layouts under Settings → Connection. The server decodes it exactly like a real uplink and nothing is stored. The Payload builder works the other way round: type real values and get the bytes your firmware must send.

Question 45

How long are console lines kept?

Accepted Answer

The last 48 hours, up to 2,000 lines per sensor. Refused requests are recorded at up to 20 per minute per sensor, so a device stuck in a retry loop cannot flood the log.

Question 46

How long is my sensor data stored?

Accepted Answer

Measurements are kept until you delete them. There is no automatic purge by age. Removing a station or its location does not delete measurements. Deleting a sensor is permanent and removes its measurements, anomalies and shares; deleting your account removes everything. Sensor data is hosted in Regensburg, Germany, within the European Union.

Question 47

Can I share my sensors with my team?

Accepted Answer

Yes. On the sensor page open Settings → Sharing and invite another registered HydroNode account as Can view, Can edit or Can manage. Can view sees readings and anomalies, Can edit can also rename and send commands, Can manage can also share, change settings and start updates over the air. Sharing does not change ownership. Only the owner can see the Secret, transfer the sensor or delete it.

Question 48

What happens when I transfer ownership?

Accepted Answer

Transfer under Settings → Transfer or delete is permanent from your side. The new owner must already have a HydroNode account and gets full control. If the sensor is a station, the station moves with it. You lose access right away, including your notifications and station follows; access returns only if the new owner shares the sensor with you. Public data stays visible to you like to everyone else.

Question 49

Is my data secure?

Accepted Answer

Data in transit is protected with TLS. Devices on WiFi sign every request with their Sensor ID, a timestamp and their Secret; LoRaWAN webhooks use a private token per account and accept only DevEUIs linked in that account. Sign in is handled by Auth0. Private data is visible only to you and the people you share it with; station readings become public only after you set a location and turn on Show on the public map.

Question 50

How do I delete my account and all my data?

Accepted Answer

Delete the account yourself under Profile → Danger Zone → Delete account in the web app, or Profile → Delete Account in the iOS app. Deletion is immediate and cannot be undone. It removes your sign in identity plus your sensors, measurements, anomalies, stations, shares, follows, registered devices, push tokens and profile data. Export anything you need first under Operations → Data transfer.