Wifi radiator valve thermostat - Eurotronic Comet Wifi

Hey community,
while looking at options to automate heating I stumbled across this fairly new valve by Eurotronic. I was surprised to see Wifi in the name.

German webpage: https://eurotronic.org/wlan-wifi/comet-wifi-heizkoerperthermostat
Random English article: https://www.gearcoupon.com/eurotronic-comet-wifi-thermostat-at-a-glance

Did anyone already test these? Any info on the chances these can be integrated with Home Assistant?


I‘m also interested in this. I can’t find any information on the protocol though…

Hey snizzle,
not much on the technical details revealed, sadly. I wrote a support mail and got the response that the company is on leave till Jan 04. Let’s wait.

Sounds very interesting. Any news from them?

Sadly the expected non-engaging response I feared for…

Sehr geehrter Herr Dietrich,

vielen Dank für Ihr Interesse an unserem Comet Wifi. Leider lässt sich unser Comet Wifi aktuell nur über die Eurotronic Wifi App konfigurieren und steuern.

Mit freundlichen Grüßen

English: “Currently only possible through our app”.

I’ll push them once again but hopes are low.

If anyone thinks of getting one and grabbing it’s network communication, be my guest! I currently do not have the time to start with such a project :-/

To bad, I was just about to buy the zigbee version when I spotted these. But these look much better + the wifi is very compelling. I think they are just a bit to expensive to buy just for experimenting and maybe find out they only work with the proprietary cloud service

Hey all together,
I have some fresh news from Eurotronic:

Sehr geehrter Herr Herzog,

vielen Dank für Ihr Interesse an unserem Comet Wifi. In den kommenden Monaten werden wir eine API veröffentlichen, mit der Sie das Gerät dann ab nächster Saison in Ihr System einbinden können.

Leider wird die API voraussichtlich erst zum August 2021 verfügbar sein. Gerne können Sie sich dann noch einmal mit uns in Verbindung setzen.

This means that Eurotronic will publish an API to implement the devices in an existing system. Unfortunately this API is going to be available in August 2021.

Some great news as I think.

EDIT (03.03.2021): I asked the support for additional information about technical details but they couldn’t give me any because they’re still in development.

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Thanks for the update! I postponed purchasing my valves till next winter So this API might be just time to also get is up and running in Home Assistant

I just bought two different models to build-in my own PBCs but with these news I’m gonna buy this professional solution in autumn.

Great news @alve89.
Let’s hope they deliver on that promise. I’ll also wait (winter is over anyhow).

I just bought one of these devices to check it out and see if maybe I can figure out the protocol and integrate it myself.

It looks very nice but unfortunately it does not connect to the app at all. Eurotronic confirmed they are working on fixing a bug in the app. I took the opportunity to inquire about the status of the API as well. the response is

'Dear Mr Bakker,

Unfortunately, I can’t tell you when the bug in the app will be fixed. As I said, we are still working on the problem. So this is no problem with the device itself.

For the comet wifi we do not have an API but maybe for the next heating season in october.

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Thanks for the update! Doesn’t sound great but keep us in the loop!

After a week or so I just tried again to set it up with the app from the store and somehow it just worked. Have not heard any updates from Eurotronlic however.

The app is pretty basic. I have not tried to sniff the protocol as I am not sure what the best way is to do so from android. Any advice on that is welcome.

Maybe start here android - Capturing mobile phone traffic on Wireshark - Stack Overflow

It will be a lot easier if it’s not ssl encrypted. Good luck!

Ok, I used the ‘WIFI hotspot on my laptop option’ which is so simple I think I should have thought of it myself.

So there is some good news and some bad news, the good news is that I can see my phone send packets with Application level protocol mqtt. The bad new is that it is sent via TLS to an Amazon Elastic Cloud server.

any news about this? Can you integrate it into HA?

There’s no news about the new API. I think this will take a few more weeks until they publish anything.

Is that based on new info from Eurotronic or assumed based on what they communicated before?

I somewhere (obviously not here, even if I thought that) a user wrote that he/she wrote again to Eurotronic and the answer was that it still takes some time.
I hopefully really read that and not only dreamed it…

Sorry I was not able to update on this.

I did find a way to control and read status information from these devices in HA. Unfortunately this relies on a security issue in the way the app currently communicates with the devices. I reported the security problem to Eurotronic some time ago and they are working on resolving this problem.

I just got the following from them

At the moment we are in the last steps of testing our new app version. This will be available within the next weeks.

The new app will work with a data base and the security problem will definitely be solved by doing so.

At the moment we cannot tell you when we will publish the API for Comet WiFi.

I expect the new version of the app will also require an update of the devices firmware after which it will probably no longer be possible to use this mechanism.