Boiler modulation + zone valve control

I would like the option to use my extension kit to control the boiler via opentherm, but still have my wired thermostats click over when that sensor calls for demand so that I can use it for my zone valves.

Really don’t understand why this isn’t an option, many home in the UK have zone valves meaning boiler modulation isn’t an option without forcing the zone valves permanently open.
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  • Vamp


    This option is already working :)

    • Connect Extension kit (or wireless Receiver) to the Boiler via OpenTherm or any other BUS.
    • Connect Phase cable to Wired Thermostat "COM" input and connect "NO" output to the Valve or Pump (any device that possible to control a relay) Phase input (brown cable). Connect the Neutral and Ground cables to The Pump directly (it also work with 12/24V DC but my Example is AC )
    • Connect both of devices to Tado Bridge.
    • Set the Wired Thermostat zone that the "Zone Controller" is the Extension kit or Wireless Receiver
    • Now it possible that you push the button on wired thermostat you see a "download settings" icon. That meen they update the configuration.
    • If it finish (you able to set the temperature) push the wired thermostat button to 3 sec. now you see the menu. now push the button 3 sec again. Now you are in the settings wizard. First setting is the relay mode on wired Thermostat. R01 is the NO , R02 is NC mode. Use R01. After You able to set the use Extension kit. Chose "Yes" (Check mark and not "X") After you able to set the Extension kit or Receiver working method (Relay or one of the Bus) if you use OpenTherm, Chose "D01". Save the Settings.
    • Now it possible that the config icon is also appear again, when you push the button. Wait that is dissapear.

    Now when you get a heating request from wired thermostat, it do two thing.

    • "Ask" the Extension Kit / Receiver to start heating via BUS
    • Turn the Relay to Close state and Start the connected electrical device.

    My experience that the heating is over, need to wait about 2.5 minute and the relay is open again and the connected device is turn off.

  • AdzLill
    AdzLill ✭✭✭
    Thank you, I will have to test this.

    But a big questions is. If this is possible, why can it not be controlled in either the standard app, or the professional app.