New binding for Wolf heating systems connected via an ISM8

I’m using openHab for some years and I like very much the principle. All my devices are mainly connected via KNX. This year I have built a new house and installed a new instance of openHab for this house too.
I have chosen a Wolf heating system and looked into the options to integrate this into openHab. The existing bindings of the e-bus did not really fulfil my needs as I’m running openHab on a Synology and I didn’t want to add a separate device for creating the physical connection to the bus. Therefor I was ordering the official Wolf ISM8 card. This card connects the internal e-bus of the heating system to the network. This card is originally designed to be used with an object server, which receives the values from the heating system and maps this info to the KNX bus. As I did not want to have all the information on the KNX (and save the money for the device), but only within openHab, I was looking into the option to have this directly integrated. After reading the manual ( I was doing some basic tests and it didn’t look too bad.

I’m an engineer and from time to time writing technical software (mainly in Windows / .NET), but not that much familiar with Java. Thus I was creating a prototype in .NET and after a short moment I was able to send and receive values from my heating system.

After having this achieved I went straight forward and migrated this into Java. I ran into some difficulties, but finally have my first own binding running and working. Yippee!

I was just asking myself if this binding is in interest for anyone and should/can be somehow made public?

In case yes, what is the normal way of doing it?

I’m sure that that the code needs some review as I was just converting from C# and changing only those things not acceptable by the compiler. Especially the handling of the bytes was in a generic list in C# much easier. I didn’t found a good replacement due to my language skills and used very much a ByteBuffer instead.

Thanks in advance for your feedback,

Always, post away

You can use the market place
Or post a pull request on gitHUB (Your code will need to be reviewed)

Thanks for your reply.
I have created the pull request.

Hello Hans,

I also have a Wolf heating system (TGS-24/200) and I’ve always wanted to integrate it into my openhab setup. My openhab is runing on a Raspberry PI and I have no knowledge of KNX so I’m looking for a simple solution.
I was thinking of changing the thermostat by a new one such as the one of Netatmo and use the Netatmo binding for the integration. The issue with this solution is that an internet connection is required as integration is done in the cloud using API. Now, it would seem that a solution could be to use the ISM8 module and the binding that you developed. Are you happy with it? Does the module speak directly with openhab without internet connection?


Hi Gaetan,

the ISM8 works without any internet connection. The card does send to a configurable partner the values of the heating system (as well as water heater and air exchanger) in case the data points are changing. In the PDF (listed in the initial description) you can find the supported data points.

I have openHab installed on a Synology. The binding require a TCP/IP connection as it opens a port and listen to incoming messages. In the web page of the ISM8 card, you need to set the IP of the receiving partner. This is the Synology NAS in my case, but in your case, you need to set it to the IP of the Raspberry.

There is no need to have a KNX system within your setup. The card is using the KNX-IP protocol to send the data points. The binding discloses all available data points as items in order to use them wherever you like (sitemap, rules, persistence …).

The ISM8 binding works so far fine, as I did not find any issues. The binding is now running for 3 months without any problems. I’m using the binding to change the set-points of the hot water and changing the operating modes. Next to this did I enable within openHab the persistence for some values in order to monitor the heating system. I’m not a heating system specialist and can’t tell you if the interface is compatible with your system.

I have created a pull request. You can download it and install it on your Raspberry.
Please check the link below:

Best regards,

Hello Reiner.
Where is the place for the download of this binding?

Dear Stouni,

currently the binding is only available as source within the pull request. You can download the source and compile this locally (the link is in the previous post). It isn’t that complicated and descripted here

After successfully compiling you can add the jar file and into your openHAB addon folder.

Best regards,


Dear Hans-Reiner,

your binding would be very helpful for my openhab setup (at the moment still 2.5) - however, trying to make the jar locally I had errors (“could not resolve dependencies”, “missing artifact”). Would it be possible to include the jar into the distribution?

Best regards and thank you, Armin

Hi Armin,

the ISM8 binding is already part of the addons. You should be able to select the binding from your setup when adding a binding. Please check this and let me know if this isn`t available.

As alternative you can download the official Add-Ons for 2.5 (, extract the jar file (openhab-addons-2.5.12.kar\repository\org\openhab\addons\bundles\org.openhab.binding.ism8\2.5.12\org.openhab.binding.ism8-2.5.12.jar) and copy the JAR to your addons folder of your OH setup. To extract the KAR file you can you 7-Zip or probably WinZip, WinRar or any other tool.

Best regards,

Hi Hans-Reiner,

many thanks for your friendly support - after downloading the jar file from the backup I could install it manually, add your demo app to my configuration, and it is working like a charm without any problem! Nevertheless, Paper UI is still showing the binding as installed and also as to install …

Thank you for your work and best regards, Armin