Wired thermostat in relay with wireless zone controller

Can I use the wired thermostat in relay mode to control an underfloor heating pump but connect it to the wireless zone controller to request for heat?

Alternatively if I put the wired thermostat in the same room with a wireless thermostat could I pair them so the wireless thermostat would control the relay function on the wired thermostat and also call for heat?


  • I’m not sure about the first part - I think it depends on how your pump is wired.

    For the second part you should be able to put a wireless temp sensor in the same room as a wired thermostat and set it as the measuring device. The wired thermostat would be the zone controller.
  • And if I were to put only the wired thermostat in the room and connect it to the underfloor heating pump in relay mode so it turns the pump on when needed, could I set for that room the zone controller to be the wireless receiver so my boiler also knows to turn on the heat?

    Problem in my case is that the underfloor heating pump its just there to circulate the water as my boiler does not have enough power to circulate it. Pump is not connected to the boiler in any way and I was currently using a Sonoff wireless relay to turn on the pump when boiler is heating.
  • johnnyp78
    johnnyp78 ✭✭✭
    edited November 2022
    I don’t think that would work. For the wired thermostat to act as a relay switch for the pump it would need to be the zone controller. Tado isn’t really designed to directly control external pumps.

    This might help but I think it’s a slightly different situation to yours https://community.tado.com/en-gb/discussion/13204/support-for-ufh-pumps

    Thinking about it, you could physically put a wired thermostat and wireless temp sensor linked to wireless receiver in the same physical room but create two separate rooms on the app. That would let you have two zone controllers for the same physical room.
  • @gugionut if you currently have a Wireless Receiver turning on the boiler whenever a Tado device requests heat, then yes you can add a Wired Thermostat to control the UFH pump. Whenever the UFH area needs heat the Wired Thermostat will turn on the pump and request the Wireless Receiver to start the boiler.

    Not sure the precise details of your heating system so do check with customer support that you can actually use this solution before you make changes.

  • @johnnyp78 thanks for recommending that other thread. It helped me a lot.

    @GrilledCheese2 just installed the wired thermostat today and after playing a little bit with the settings I made it work. The wireless thermostat is the temperature sensing device, wired thermostat is in relay mode controlling the UFH pump and the wireless receiver is the zone controller.

    Running some simple tests by manually adjusting the temperature it looks like everything is working. Unfortunately after leaving the room on smart schedule with early start on the pump didn’t start. Disabling early start fixed the problem but after a few minutes the pump was stopped by the wired thermostat while the room was still calling for heat.

    This first setup was with Ek Off and relay mode. I then tried with Ek On but it would keep the relay always on.

    Now I’m back to Ek Off and relay, did the setup from scratch after the firmware was updated and from simple tests looks like it’s working, fingers crossed.

    Update 1: the wired thermostat closes after about 5 min every time, while the room is still calling for heat.

    Update 2: Using the Tado for Professionals app I figured out that there was a configuration issue. It looked like there is an OpenTherm connection but the zone controller is the wired thermostat on relay mode. What ended up happening is that both thermostats were competing and were canceling one another. Looking at the boiler, it was stoping/resuming heating every few minutes. Warning sign on wireless receiver was on when this was happening. In the app everything looked good.

    Doing the setup again on both thermostats and making sure to set HC01, HW On, Ek On, D01 on both. Wireless set on TS and wired on R01. Just ran the system for 30 min and everything is working. Everything green in the system check on Tado Professionals app.
  • Finally found the proper guide to make everything work. The correct way to do it in my case is described at number three: https://cdn.brandfolder.io/607DGEMS/as/5fczjjnv4q4kq74hfshwqrht/Draadloze_Slimme_Thermostaat_Handleiding_-_vloerverwarming_en_radiatoren.pdf

    Unfortunatelly there is no english version but the whole idea is to only configure the wired thermostat and the wireless one you just pair it and will be automatically configured.

    I did a factory reset on both thermostats and the followed the guide and everything works now.

  • Dear Gugionut,

    I would like to do the same setup, may I ask how do you config it in the Tado app? Is the Wired Thermostat put as the zone controller in the Wireless Thermostat and the Wireless "Receiver" put as the zone controller of the Wired Thermostat?


  • @brianlai in order for this to work you need to do the initial setup only on the wired thermostat. The thermostat will control the UFH pump in relay mode and communicate with the wireless zone controller that is the device that connects to your boiler. When everything works you can add the wireless thermostat to this setup and set it in the same room in the app as the wired thermostat. After they are both in the same room you will just need to set the wireless thermostat as the measuring device for that room.