Advice for cloudless thermostat

Hello everyone,
I have some small experience with openhab (I did some automation on a meeting room) and I need your advice on a thermostat: I’ve bought a new home and I’m re-doing all of its electrical system, I’m not looking into any automation for lightings & co, but I’d like to have maximum control over my heating system.
The house has 7 rooms and had 3 basic thermostat that controlled 3 zones (cameras, bathrooms, living).
I wanted to install thermostatic radiator valces (TRV) on all of the 7 heaters, but then the local Honeywell reseller made me think about it, and instead of using a battery powered TRV I will split the heating circuit in more zones: each camera, each bathroom, and one for living/kitchen.
I already added the needed electrical conduit so that each room can have its thermostat (so that would be 6 in total), while I’d like to use 2 additional wireless TRV for the living area (where I couldn’t adapt the conduits).
I was looking at something like tado° but then I realized that I don’t want to be dependant on a cloud service to run my heating. I’d like to get some simple chronotermostats that can be later integrated in openhab, so I can get my house heating in no time and take all the time I need to interface them with openhan and do fancier stuff.
Any suggestion? I’ve no preference for the protocol, it could be cabled or wireless, the unit shoul be 220V powered and also include a humidity sensor (so I could start automatically the extracting fan in the bathroom when I’m having a shower)


MAX! have a cloud interface but will also run cloudless, there’s a OH binding for the cube.
Short of any subsystem to coordinate the thermostats, you could also deploy single ZWave or WiFi powered units and do the programming yourself.

Have a look at innogy from Rwe.
Do you mean 220V for your controller or for your valves?

Don’t add a complete ecosystem just because of the valves.

If you really want to have maximum control, you could also use decomposed thermostats, i.e. valves you usually use for underfloor heating, and any kind of temperature sensor. Drawback is you need do program the basic on/off functionality yourself, and it won’t work when OH is down.

I wanted to do something similar, so came up with this: My Central Heating Solution using Thermal Actuators

Although I had the Nest at the time, it was just a glorified on/off switch, so could easily be replaced by another Sonoff or relay to just switch the “call to heat” on the boiler.

For a fully wired solution, the thermostat functionality within the Velbus glass panels is really good.

There is a great binding for openHAB which gives full access to the thermostat.

All you’d need is a glass panel in each room and a channel of a relay to activate the valves.

If you’re lucky enough to have suitable TRV valve bodies on your radiators, you can replace the dumb actuator heads with

24vdc or

220vac wax thermal actuators, just like the ones used on under floor heating manifolds.

If you use 4 wire actuators instead, you can connect them to the heat call of your boiler, so that your boiler will only come on when a valve is fully open.


Thermostat controls the valves

The microswitch in the valves control the boiler.

If you have a interlock relay between the actuator switches and the boiler heat call, you can easily configure a daily valve movement so that your valve pistons don’t stick during the summer, without the boiler being fired.

Example wiring plan PDF

If you don’t have any intention of controlling anything but heating, it’s a simple process to create actions for the buttons on each glass panel to affect its own thermostat.

For example.

If you choose the bottom of the range single button glass panel Black or White, with or without programmable back lights, you can program the button to put it’s thermostats into a boost state (until the next timed event or for a pre-defined time).

We have done this for a (public venue) client who didn’t want a thermostat that could be tampered with.

However, they did want an easy way to boost the heating for each zone.

Hello everyone, thanks for all the quick answers, I’ll try to look at them one by one:

I think that this would be the product , it would be nice as it’s super cheap (26€ each) but I think it can only control the radiator valves, so there’s no way to control the “zone valves” natively (sorry I’m italian, I have no idea how these are called)

It’s battery powered so that’s also a limit for me ( I would have 6 of these, so I’d like not to have to change batteries if possible). Anyway I think it would be a nice staring point to integrate it in openhab and the doing the valves control in openhab.

This one ? Their website is only in German or am I missing the english version?

@mstormi and @Confused yes that would be nice, but I can’t risk to froze my wife just because openhab is offline (well maybe in the future I could risk it, but I’m still to newbee right now). I’d love to be able to take something already working (like MAX!) and be able to extend it with openhab.

@MDAR the Velbus solution seems interesting, I can’t understand how much is already pre-built and how much programming effort would be needed. I see that the smallest unit is around 80€, It could read the temperature and have a single button to act as a “boost” signal, then I would need 8 channe relay to open the valves/boiler for the relevant room. The unit with a display is 200€ / 250€ . So I could have a main unit where I see the temperature readings and set the schedules, while a basin one on each room?


I read there’s also a generic MAX! plug socket, so you could add these and plug in electrothermic actuators to run your underfloor loops.

Some food (video) for thought…

Ran across this the other day…while it’s HomeAssistant aimed…it walks through building a cloudless smart thermostat with a D1 mini, a couple of relays and a temp/humidity sensor.

Just thought I would pass along,



The programming for your application would be minimal.

The “heater” channel of each thermostat would require a single “Follow” action to the appropriate relay channel.

A button would need an action to its own (or other/s) thermostat to activate the Comfort (boost) mode.

If you want the daily valve movement, you’d need an interlock relay and an extra ‘action’ per thermostat and activate the ‘anti jamming’ feature.

Finally, the Oled would just need to be told which other thermostats you want to display / control.

After that, it’s only a matter of creating the time profiles in each thermostat to suit your needs.
This can be simple or complex as you want.

Use the Oled panel to control everything, or give each panel its own profile.

I have a demo rig in my office that you are welcome to connect to using the free VelbusLink programming software.
If you want to investigate the functionality before making any commitment.

Regarding pricing, if you don’t have a local reseller, I’m able to process an order with shipping direct from the manufacturer.

Using openHAB, you can create whatever UI you want.

I’m not a very good graphics designer, so my UI is very simple.

Some of my clients have created amazing interfaces.

I use a widget that @tomvancutsem created.

Hello everyone,
In the meantime I’ve found out which actuator my plumber is going to install.
I think I will install one of these actuators for each radiator, reuse the existing antique thermostats and then implement sensors & co in openhab (and eventually velbus)

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Thanks for the hint, I was finally able to watch the video, it’s very interesting but I still don’t have that much practice/convidence in openhab & co to run my full heating system on it :slight_smile: I will try to go with velbus integrated in openhab. But will definetly add something like that in the future, thanks!