Scrapping an ISG Web with node-red

This respository contains the required Node-RED flows to scrape the web interface of a STIEBEL ELTRON Internet-Service Gateway (ISG WEB) and forward the data via MQTT to HA (and optionally to an InfluxDB).

For questions and other inquiries, use the issue tracker in this repo.

History

After I extended my home installation with a photovoltaic converter of SMA and connected the installations (Stiebel Eltron LWZ504e and SMA Sunny Manager), Modbus was not working anymore on the ISG web and I could scrap my old scrapping method (python-stiebe-eltron). The Modbus and EMI “modules” can not run in parallel on the ISG web. The complete history of the marriage between Stiebel Eltron and Home Assistant can be found in this thread, including different solutions: Is there any interest in a Stiebel Eltron climate platform?

Requirements

At minimum you need the following components:

• STIEBEL ELTRON Internet-Service Gateway ISG WEB
• STIEBEL ELTRON heatpump (compatible). Successfully used devices:
  • LWZ504e
  • LWZ304
  • Tecalor TTC05
• Node-RED, either installed as part of Home Assistant OS as an Add-on, as a separated docker container or as any other possible deployment option.
• MQTT Broker, either installed as part of Home Assistant OS as an Add-on, as a separated docker container or as any other possible deployment option.
• Network connection bewteen all components

The setup can easily be extend with the following components to get very nice history graphs.

• InfluxDB
• Grafana

Installation

1. Setup Home Assistant (HA)
2. Setup the MQTT Brocker
   1. Add MQTT integration to HA
   2. Make sure HA is able to receive MQTT messages
3. Setup Node-RED
   1. Import 2 relevant flows in this repo into Node-RED. The default flows are flow_ha-mqtt-discovery.json and flow_stiebel-servicewelt.json, the *Tecalor-TTC05.json flows are for Tecalor TTC05 and compatible devices.
   2. Without InfluxDB: delete the nodes which prepare and send the data to InfluxDB. You don't need them.
   3. Update the node "Set ISGWeb URL" in flow "Stiebel Servicewelt"
   4. Update the node "HA MQTT Set device details" with your installation details in flow "HA MQTT Discovery".
   5. Verify or add the MQTT broker configuration
   6. Deploy the flows
4. In HA
   1. Add the MQTT integration
5. In Node-RED
   1. Trigger the node "Trigger to flush messages to get HA discover new sensors immediately" in flow "HA MQTT Discovery".
6. In HA
   1. Check for new sensors

Resolve issues

In HA, if you did setup MQTT, you can go to "Configuration > Integrations > MQTT > CONFIGURE" and start listening to the topic "homeassistant/sensor/#". You should see a bunch of messages, which start with something like "homeassistant/sensor/...".

If you don't see them, go to node-red again. The debug panel will only show something, if an error occurs or if you did enable debug msg nodes. You can do so in the "HA MQTT Discovery" flow. Then redeploy it and you should soon get some messages showing up in the node-red debug log.

• In case you see the messages, but still do not receive anything in HA, it's probably your MQTT broker config in node-red, which is not working.
• In case you don't see any messages, copy the debug node in "HA MQTT Discovery" and attach it anywhere earlier in the flow to find if somewhere the messages are flowing.

License

The content of this node-red repository is licensed under MIT, for more details check LICENSE.