Control room temperature with radiator thermostat in another room

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1

Ok, my problem is this. The picture shows two thermostat besides each other. The left one is attached directly to the radiator in the current room.

The one on the right controls the floor heat in the next room, but since the thermostat is in the current room, it changes heating based on the temperature in the current room.

Now, if i tropiske the thermostat with a Zigbee thermostat, can I then get it to work, based on the temperature sensor in the other room?

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2

Yes you can do. I do something similar with one of my radiators (not using Zigbee, but ZWave, but the principle will be the same)

You need a simple temperature sensor in the room you want to control (zigbee, zwave, mqtt, doesn’t really matter, as long as you can have the temperature available in home-assistant).

You need a zigbee/zwave thermostat replacing the existing thermostat in the adjacent room.

The problem is that this thermostat measures and acts of the temperature in that room, what you don’t want.

To overcome this:

  1. Create a helper-switch entity (on/off or toggle).
  2. Create an automation, if helper switch is on, set the set-temperature of the new thermostat to 25 degrees (so thermostat fully open) and if the helper switch is off, set temperature to 10 degrees (thermostat closed).
  3. create a climate helper, input entity is the temperature sensor, output/switch entity is the helper switch.

In this way, the “own/self measured temperature” of the thermostat in the room you don’t want to control is overruled, the new thermostat is just used as an on/off valve, which is controlled by the temperature sensor in the room you want to control.

3

Great - I’ll give it a try! Thanks a lot! :blush:

4

Hi Jesper, if you’re looking for zigbee TRV’s, have a look at Sonoff TRVZB