Frequently Asked Questions (FAQ)
Installation & Setup
1. How do I install the WaterP1MeterKit?
Detailed installation instructions can be found in the Installation Guide. We also have installation videos on YouTube for popular water meter brands.
2. Which hardware version do I have?
Since October 2025, we only sell the V3 — the latest and most feature-rich version.
How to identify your version:
| Version | How to Recognize |
|---|---|
| V3 | Has a small cutout/hole on the side (lengthwise) for the expansion sensor port |
| V2 | PoE works — no side cutout (V1 and V2 look identical from outside) |
| V1 | PoE does not work — no side cutout (V1 and V2 look identical from outside) |
👉 See our Hardware Versions page for more details and a complete feature comparison.
3. What connectivity options are available?
All versions support WiFi and Ethernet. V2 and V3 have built-in PoE support. The device ships with WiFi firmware by default — you can switch to Ethernet using the Firmware Type selector in Home Assistant or by flashing via USB-C. See Network Configuration for details.
4. How do I switch between WiFi and Ethernet?
There are two methods:
- Via Home Assistant: Use the Firmware Type selector (connect Ethernet cable first when switching to Ethernet!)
- Via USB-C: Flash firmware using the web flasher
⚠️ Note: Switching from Ethernet back to WiFi requires USB-C flashing — the selector only works for WiFi → Ethernet.
See Network Configuration for detailed instructions.
Water Monitoring
5. Can I use the WaterP1MeterKit to measure only water consumption?
Yes! You can use the WaterP1MeterKit to measure water only, energy only, or both. Simply connect the appropriate sensor(s) and disable any unused entities in Home Assistant.
6. How does the WaterP1MeterKit measure water consumption?
The WaterP1MeterKit works by placing a sensor on the 1-liter indication of your water meter. There is a metal plate inside the meter that completes one full rotation for every liter of water used. The kit measures the position of this metal plate to determine the flow rate.
7. Which water meters are compatible?
The WaterP1MeterKit is compatible with most analog water meters that have a rotating metal plate indicator. This small metal disc (usually silver-colored) rotates once for every liter of water used. Our sensor detects this rotation via magnetic detection.
⚠️ No rotating metal part? Unfortunately, our sensor will not work with your water meter.
Compatible Brands
| Brand | Holder Type |
|---|---|
| Sensus | Standard holder (with screws) |
| Itron | Standard holder (with screws) |
| Elster / Honeywell | Standard holder (with screws) |
| Actaris | Standard holder (with screws) |
| Schlumberger | Standard holder (with screws) |
| Diehl | Special clip-on holder (no screws) |
| Zenner (ETDK ZR, ETWD, ZR) | Universal holder (with tape) |
| DH Metering | Universal holder (with tape) |
| Hidroconta | Universal holder (with tape) |
| Maddalena (Plus C, MVM) | Universal holder (with tape) |
Holder Types
We include the appropriate holder based on your water meter brand:
- Standard Holder: Attaches with screws to the water meter adapter plate
- Diehl Clip-on Holder: Simply clicks onto Diehl water meters — no screws needed
- Universal Holder: Uses double-sided tape for other water meter types
Installation Videos
📺 Watch our installation videos for the most popular water meter types:
| Video | Water Meter Types |
|---|---|
| Type 1 Video | Itron / Actaris / Schlumberger |
| Type 2 Video | Sensus |
| Type 3 Video | Elster / Honeywell |
Not sure if your water meter is compatible?
Send us a photo via Contact or chat live on Discord — we're happy to help!
8. The sensor doesn't detect water flow. What should I do?
- Check the sensor position — it needs to be exactly over the 1-liter indicator
- Adjust the position slightly (sometimes just 1mm makes a difference)
- Ensure the black side of the sensor is facing upward
- The green LED should flash once per liter of water used
See Troubleshooting for more solutions.
9. How does the water meter tracking work?
The WaterP1MeterKit stores your water consumption persistently:
| Sensor | Description |
|---|---|
| Water Total Consumption | Pulses since boot — use this for Energy Dashboard |
| Water Meter Initial Value | Set your current physical meter reading |
| Water Meter Total | Initial Value + Total Consumption = actual meter reading |
Your data survives reboots and firmware updates!
10. When is water data saved?
The kit uses smart saving to protect flash memory:
| Trigger | When | Always Saves? |
|---|---|---|
| Interval check | Every 5 minutes | Only if 50+ liters difference |
| Shutdown | OTA, restart, factory reset | ✅ Always |
Maximum data loss during unexpected power outage: ~50 liters (0.1% of yearly consumption).
11. Can I disconnect the water sensor?
Yes! The connection method differs by hardware version:
| Version | Connection | How to Disconnect |
|---|---|---|
| V3 | Connector plug | Simply unplug the connector |
| V1/V2 | Screw terminal | Open enclosure, unscrew the 3 wires |
For V1/V2: Carefully unclip the housing, locate the screw terminal with 3 wires, and unscrew them. Take a photo first to remember the wire color order!
12. Can I extend the sensor cable beyond 3 meters?
Not recommended. The sensor cable is 3 meters long. Extending it causes voltage drop, resulting in unreliable readings or complete data loss.
Need more distance? Instead of extending the sensor cable:
- Install the WaterP1MeterKit as close to the water meter as possible
- Use an Ethernet cable (up to 100m) for the network connection
Ethernet cables are designed for long distances without signal loss — much better than extending the sensor cable!
⚠️ Any cable extension is at your own risk and not covered by warranty.
Energy Monitoring
11. How does the WaterP1MeterKit measure energy consumption?
The WaterP1MeterKit uses a P1 meter cable connected to the P1 port of your energy meter. It reads all data transmitted by the energy meter, including:
- Total consumption (kWh)
- Instantaneous power usage (W)
- Voltage and current per phase
- Gas consumption (if connected to meter)
12. Does it measure solar panel feed-back to the grid?
Yes! The WaterP1MeterKit measures all data transmitted by your energy meter through the P1 port, including energy fed back to the grid from solar panels.
13. Which energy meters are compatible?
The WaterP1MeterKit supports DSMR/ESMR meters version 2.2 to 5.0. Most Dutch and Belgian smart meters are compatible.
⚠️ Important: Only the P1 port works. Some meters also have an MBus port — this will NOT work with the WaterP1MeterKit.
14. Can I use only the P1 meter without the water sensor?
Yes! Simply don't connect the water sensor and disable the water-related entities in Home Assistant.
Power & Connectivity
15. What power options does the WaterP1MeterKit support?
| Power Option | V1 | V2 | V3 |
|---|---|---|---|
| USB-C (5V ⎓ 1A) | ✅ | ✅ | ✅ |
| PoE (802.3af) | Via splitter | ✅ Built-in | ✅ Built-in |
16. What is the difference between the USB-C and PoE options at checkout?
This choice determines which firmware is pre-installed:
- With USB-C Adapter Set: WiFi firmware installed, Ethernet port disabled
- Without USB-C Adapter Set: Ethernet firmware installed, ready for PoE
You can always switch firmware later. See Network Configuration.
17. How do I know which firmware is installed?
Look at the Ethernet port LED:
- Green LED on (without cable connected) = Ethernet firmware
- LED off = WiFi firmware
18. Does the WaterP1MeterKit require internet access?
For normal operation: No. The WaterP1MeterKit works 100% locally. All sensor data stays on your local network.
The only external communication is for firmware update checks (version number only — no sensor data is transmitted).
Home Assistant Integration
19. How do I connect to Home Assistant?
- Power on the device
- WiFi: Connect to
waterp1meterkithotspot (password:waterp1meterkit), configure your network - Ethernet: Connect via RJ45 (Ethernet firmware must be installed)
- Home Assistant automatically discovers the device via ESPHome
See Installation Guide for detailed steps.
20. How do I add the WaterP1MeterKit to the Energy Dashboard?
- Go to Settings → Dashboards → Energy
- Add
Water Total Consumptionas water source - Add the appropriate energy entities for consumption/production
See Usage Guide for detailed configuration.
21. The device is not discovered in Home Assistant
- Ensure the device is connected to your network (WiFi or Ethernet)
- Check that Home Assistant and WaterP1MeterKit are on the same VLAN
- Try adding the ESPHome integration manually by IP address
- Check your router's DHCP leases to find the device IP
Sensors & Accuracy
22. What sensors are included?
All versions include:
- Water sensor: Pulse counter for water meter
- P1 reader: RJ12 connection for energy meter
- Temperature & humidity: HDC1080 sensor
V3 additionally supports expansion sensors (water leak, door/window).
23. How accurate is the water measurement?
The WaterP1MeterKit counts pulses from your water meter's 1-liter indicator. Accuracy depends on correct sensor positioning. V3 has improved precision hardware.
24. The temperature/humidity readings seem off
The HDC1080 sensor is located inside the device housing. Readings may differ from room temperature due to:
- Heat from electronics
- Location (often in basement/utility room near water meter)
For room climate monitoring, consider a dedicated sensor like the UltimateSensor Mini.
Expansion (V3 Only)
25. What expansion options are available on V3?
V3 has an expansion port that supports:
- Water leak sensor: Detect water leaks near your water meter
- Door/window sensor: Monitor access to utility rooms
26. Can I add expansion sensors to V1 or V2?
No, only V3 has the expansion port. V1 and V2 do not support additional sensors.
Firmware & Updates
27. How do I update the firmware?
Two options:
- Via Home Assistant: Enable the Update entity, check for updates, install OTA
- Via ESPHome Dashboard: Click Install/Update
Updates are delivered Over-The-Air (OTA).
28. Can I customize the firmware?
Yes! The WaterP1MeterKit runs ESPHome. You can:
- Adopt the device in ESPHome Dashboard
- Modify the YAML configuration
- Add custom sensors or automations
- Deploy changes OTA
Source code: GitHub
29. Where can I find the latest firmware?
- GitHub: github.com/smarthomeshop/waterp1meterkit
- Web flasher: smarthomeshop.io/en/firmware
Warranty & Support
30. What is the warranty?
Please refer to our Warranty and Support page for detailed warranty information.
31. Where can I get help?
- Check the Troubleshooting guide
- Join our Discord community for peer support
- Contact us via smarthomeshop.io/contact