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Replacing the Honeywell CM707 that has only two wires


I have just bought a tado smart thermostat + starter kit + Valve radiators. while going through installation videos i have got confused as all of the videos are showing either having 3/4 wires or N L L A B C type of wiring. My home wiring seems to be simpler, on further reading i understood that this one is a heating only furnace (excuse me if i am getting the terminology wrong).

I have two questions;

  1. Is the Tado Suitable for such a wiring
  2. If Yes, then how should the wiring look when i install the Tado.

I am attaching pictures of my set up, and the tado for reference.



  • _Marie_Marie | Moderator

    Hello @DeePallavi,

    Thank you for your request.

    Please contact our technical support via the chat on our website (tado.com) with the exact make and model of your boiler/current thermostat, so they can help you with the wiring.

    Best regards,

    Your tado° Team

  • I went through the installation as per the step by step instructions and i must say it was pretty easy, even for a novice like me.

    Tado was perfectly suitable for my set up, the onscreen installation guide is very detailed

    The ‘B’ wire in my original set up went to ‘NO’ in tado
    The ‘A’ wire in my original set up went to ‘COM’ in tado.

    Dont forget to switch off the boiler and remove the fuse / power breaker.
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