Replacing Honeywell CM67i


I'm trying replace Honeywell CM67i with Tado, but I can't find correct cable.

Best Answer

  • AlexSands
    Answer ✓

    thank you very much.

    The Tado support suggest me this.

    To replace this CM67i, you must put the 2 wires in COM and NO in the tado° thermostat—ideally the A wire in COM and the B wire in NO.

    In your reply you call wire "PERMANENT LIVE feed" and "SWITCHED LIVE feed", but I found no mention of which labels correspond to in Tado's terminology.

    The "ideally" word scare me…
    The neutral is necessary' Because in another timeswitch  I found always 2 cables NO and COM, but no neutral.




  • AlexSands

    I'm so sorry, but I send this question incomplete.

    Thank you for your help.


  • policywonk
    Sorry. Presume you need to swap the wiring. According to this:
    ... there are three pins.
    A is the PERMANENT LIVE feed from your mains supply.
    B is the SWITCHED LIVE FEED from the timeswitch to the system.
    C is the point when the timeswitch has parked the live feed, turning all power off.

    The photo is a little worrying, as there are two purple wires, which makes no sense. So you have to be very careful when swapping the timeswitch with a tado controller.
    1. Turn off all power to those wires.
    2. Test that there is no power in them.
    3. Carefully tag the one on the left ( the A PIN) as the PERMANENT LIVE feed, then tag the one on the right (the B PIN) as the SWITCHED LIVE feed.
    4. You still need to locate Neutral, probably that will be found in the wiring at the boiler.
    With access to LIVE, SWITCHED LIVE, and Neutral, you have enough to make the swap.