Very good news and thank for your work! Sure I’ll test and report to you! thanks!
Very, very good news for all the others, if this solutions uses Modbus… Unfortunately 
A few weeks ago I learnd that my configuration - Stiebel Eltron ISG with special software to communicate with the Sunny Home Manager - is not able to speak with any other device over Modbus 
So I don’t think that I can help and test here … So sad …
I just purchased a Sunny Home Manager as well. What’s the issue with combining the ISGWeb with the Sunny Home Manager? Is the Sunny Home Manager blocking the Modbus port on the ISGWeb?
Don’t know exactly which protocol they use, but I have a special EMI software on the ISG so that ISG and Sunny Manager are able to communicate and that’s the problem. Was already in contact with the Stiebel support and they said that both (EMI software and Modbus) is not possible. Sooo bad…
Is there a way to integrate a login. When i go to the IP of the ISG I need to login to the servicewelt… Or am I not using this proparly?
Hi,
Thank you so much for implementing the support for stiebel eltron. I have a WPC 5 and would like to control it from home assistant. Currently I do not have the ISG web, but I would buy it for around 650CHF.
Prior to buy: does anybody have tested the integration with any WPC? I just need set the target temperatures of the hot water and the heating.
Possibly also monitoring the temperatures.
regards
Daniel
I would assume, that the WPC5 in combination with the ISG web does provide the same modbus interface as my LWZ504e - give or take some values. See the following compatibility overview.
Configuring the hot water target temperature is not possible, because it was implemented as a HVAC device and not as a water heater device.
I am not able to further support the Stiebel Eltron integration, because my ISG web is communicating with the SMA Sunny Manager - which disables modbus on the ISG web completely. Having both enabled is not supported according to the Stiebel Eltron support. It would be nice, if someone is interested to take over the integration.
Due to the modbus issue, I looked into Node-RED and requesting values directly from the ISG web interface and stream it via MQTT broker to home-assistant. It actually works quite well, and I assume changing values via Node-RED would be possible as well.
@jeanbart: Yes, ISG web has the possibility to enable the user/password access. However, I don’t know if the user is/can somehow be used for modbus.
Thank you for writing back.
Yes, my WPC5 is in the compatibility overview listed.
So if my WPC, I just control the floor heating temperature, but the water not.
One approach to solve this would be to add water heater also to the HVAC device (not beeing a true HVAC anymore), so create a HVACB (boiler) device - what are the chances to get this?
And in addition to link the interfaces for the water heating of the stiebel eltron to that new HVACB.
I have some basic programming skills but no idea about the whole framework used for home assistant.
regards
Daniel
Hi all,
I thought I’d offer some input on the approach I am taking with Stiebel Eltron climate control. I have not been able to use the current Stiebel Eltron climate platform, as it is built for a different controller.
My system is based on the WPL25 air to water heat pump, which feeds into an 800 L storage tank (SBS 801), which then provides both hydronic heating and domestic hot water. The system is controlled by a WPM3 controller and I have the ISG Web with modbus module to interface it.
Because I could not use the Stiebel Eltron climate platform, I have instead built monitoring and control using modbus sensors, binary_sensors and scripts. This has provided me with fantastically granular monitoring and control - I can see and do pretty much anything I want.
If you are interested, you can see what I have done at this Github gist. I think it should work for anyone using a WPM3 controller without modification (other than setting the ISG Web host address).
I have plans for further scripts, for example a boost function for manipulating immediate heating of either hydronic or DHW, a pasteurisation routine (the inbuilt function is terrible) and better adaptation to seasonal temperature variations. I have also built a better summer mode than the inbuilt function. All of these things are / can be built as automations / scripts making use of the control scripts in the gist.
Hope it helps someone!
Is there a way to connect a LWZ304 over RS232 with home assistant?
Hi Nick
I like your work. I have a Stiebel-Eltron LWZ 504 that I would like to control in the Home Assistant.
I took over your config data and tried it out. The entities do not have a unique ID.
My question is: what kind of heat pump do you have?
Can I take over the data 1: 1? if yes, where should the config be saved. Sorry about my English. I’m from Germany.
It would be nice if you could help me.
Thanks
Hi RashHour74,
Your English is much better than my German!
So I have a WPL25 air to water heat pump connected to an 800 L storage tank (SBS 801), which is all controlled by a WPM3 controller. The WPM3 is connected to the ISG Web, which is how I interface HA.
From what I understand, you should be able to make use of the same approach as me to control your LWZ504, but the config will be quite different, as the modbus registers are defined differently.
If you take a look at the ISG modbus guide, you’ll need to take a look at section 7, which covers your model. Block 1 and 3 registers will be used for modbus_sensors.yaml. Block 3 registers can be referenced to update bitmaps used for state_sensors.yaml. And Block 2 registers can be used for control.yaml.
It’s quite a bit of work, but mostly straight forward (and repetitive) copy and paste. Each row in the table is an entity in the config. You need to check the datatype column to get the right scale factor and so on.
Where to save the config is up to you, but I use packages for most of my yaml config. I have these yaml files in one of my package folders.
I can’t find a current web reference to the ISG modbus guide, but here’s one I found earlier. Unfortunately, I deleted the German language pages!
What is the advantage of using modbus over simple HTTP requests to the ISG gateway?
curl --silent "http://servicewelt/?s=1,0" | grep -A 1 AUSSENTEMPERATUR
<td class="key">AUSSENTEMPERATUR</td>
<td class="value">5,4 °C</td>
This is very basic, of course, but it seems to me that I can get all the data without buying the modbus feature from Stiebel Eltron, no?
Hi stucki
There is no real benefit beside having a direct integration in HA. After I extended my 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 - which by the way was free for me (you could try your luck with the Stiebel support). The Modbus and EMI “modules” can not run in parallel on the ISG web. Currently I am using a self developed NodeRed flow, which polls the web UI, feeds the data into an InfluxDB and distributes it over MQTT. HA receives it via MQTT. And as a little beauty addon the data is visualized in Grafana.
Would you mind sharing your node-red flow? I had one in the past, but I lost it somehow.
I use also the EMI module. The whole “Smart Home” thing of Stiebel is not really the best they did. Did you recognize their new app? Was pretty cheap in the first day - they tried to sell it for 29,99€ and no I am not kidding. After a few weeks the price got down to 1,99€ so I thougt: hey let’s try it. Guess what: the app and the EMI module doesn’t work together …
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Hi,
I have just had a WPF 13 S GSHP installed with Tado radiator Valves.
I am new to Hassio
I have the valve info graphing in Grafana.
I am keen to get the info from my ISG servicewelt.
I called uk technical support and they say their is an annual charge for Modbus. They will contact Germany and get back to me. Is anyone else paying for this service?
I have started a Node-Red flow based on the one posted by @fucm, but in English and can share when I get it working.
A modbus register read and write sounds like the easiest method, as scraping a webpage feels like it will require continuous updates.
They got back to me and enabled Modbus free of charge. I have been able to read back some registers with Node-Red “Modbus Read”. Is their an easier way of getting the sensor data into Hassio?
Hi fucm,
thank you very much for sharing! I just had a look into it and it is really great, I really like it! Too bad I couldn’t check this earlier but I was just too busy with other things.
Hi @cool2bdave, the data scrapping with NodeRed is actually quite stable. They do not modify the front end a lot and after failing with Modbus completely (because its just not available in case you use the energy management function) I switched to NodeRed. At the end, I really prefer NodeRed, because it gives you so much more power over the data and allows many additional functions, in a very simple way (after a learning phase). Lately, I just added MQTT discovery and I could get rid of all the manual yaml MQTT sensors (with adding for additional nodes).
Hi @azrael783, I am glad that it works for you.