Homey Community Forum

Connecting VThermo to a physical thermostat - is it possible?

Hello! Is there any way to assign a VThermo thermostat to a physical smart thermostat - say a Nest?

I have a number of electric heaters connected to VThermo via smart plugs and running on schedules but it would be cool to actually have a physical thermostat in say, the living room, that could manipulate the temperature. Any idea if this is possible with Homey? (Or even Home Assistant perhaps?)

Do you want to control your Nest with VThermo or the other way round?

Yes, essentially I’d like to control VThermo with a Nest thermostat (I have a couple kicking around from my old house gathering dust). VThermo is currently managing 4 different electric Mill heaters which are plugged into IKEA smart switches because the WiFi chips in the Mills are garbage.

I suspect this probably isn’t possible but just wanted to test the theory out…

It is possible both ways (didn’t know that yet, found out while fiddling with it :wink: )

Without a flow needed, I coupled my Tado thermostat with a VThermo.
Open the settings of your VThermo, and look for Target temperature in the same zone

  • Ticking the upper box sends the target temperature from other (hardware) thermostat(s), to VThermo in the same zone.

  • Ticking both boxes sends the target temperature to other (hardware) thermostat(s) in the same zone, and vice versa. They both follow eachother.

  • Ticking the lower box only sends the VThermo target temperature to other (not VThermos) hardware thermostat(s) in the same zone.

Functionality showed here: https://youtu.be/gV9X9aMx8b0

Hope this is what you were looking for.


Ah ha, that’s interesting to know. I don’t think this would work in my case though as I guess the Nest needs to be plugged into a compatible heating system to work. It’s not compatible with electric heaters.

I’m unfamiliar with the Tado system. Can it work as a WiFi thermostat independent of a particular heating system?

Idk about Nest, but my tado can be disconnected from my heating system, and it just works as before. The only thing not working is the heating system it should control.

Do you think a Nest doesn’t function without a HS connected? I would give it a try.

A tado is a Wifi Cloud enabled system. The Homey app ‘talks’ to it using wifi & cloud, and vice versa.
It should run without a HS connected.

Cool, Tado sounds pretty versatile! With the Nest, I don’t even know how to get power to it without connecting it directly to a heating system. It’s not battery powered which I’m assuming the Tado is?

Doesn’t need to be, it just needs to send the target temp you chose, to your Vthermo. VThermo controls the electric heaters?

Yeah, fair. That’s exactly what I want it to do. So I guess I need to figure out how to power up the Nest. I’ll need to dig it out, I seem to remember to there was a USB port on it. Perhaps that could be a start…

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Owww I did think about that, but assumed it could be battery powered. It should run on a 9V adapter (but check the needed voltage beforehand).
tado is battery powered only. You can stick it anywhere you like. There’s even a buro-stand for it.

Right, so I’ve made some progress! Dug one of the Nests out of the basement and confirmed that it has a USB socket which, I think, might able to power it. It had enough juice left in it that I actually managed to pair it with Homey but then it promptly died before I could play around in VThermo.

The only difficulty I forsee (and it’s fairly major) is that the Nest is in two pieces - the front which has the screen and sensors and a back plate which contains the connection sockets for where you plug in the wiring if you were to connect it to a HVAC system. When the two parts are connected the USB port is inaccessible… And it’s yet unclear if they need to remain connected for the thermostat to function just enough to work with VThermo.

Will need to wait for the built-in battery to charge up a bit to see… But I’m not optimistic haha

It looks like one can charge a Nest, but it has to be disconnected from the heating system then? :thinking: That’s weird.

But, in your case that’s not an issue.
Idk how Nest connects to wifi/Homey, it probably runs also via WiFi/Cloud.
You could try if it’s online while not mounted to it’s backplate

Any progress?

sadly no. if it’s not mounted to the backplate it refuses to work. I’ve gone ahead and ordered a ribbon micro USB cable from Ali express to see if I can plug in power with the mount still attached. will report back in a couple weeks when that arrives

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