Installation - Bridging the old wireless thermostat receiver

Help! Installing Tado V3 today. HW works fine but I am unable to find instruction on bypassing my old wireless CH thermostat receiver to enable TADO control of the boiler for CH.

Receiver is a Plumb Center BDR91 (see photos). Exam question is which wires do I join and which should I blank off? (frustratingly not covered in TADO's easy installaion instructions).

Many thanks in advance

Best Answer

  • Montage
    Montage ✭✭✭
    Answer ✓

    Ok. I don’t know what you’re doing with the wiring anywhere else. If I tell you to connect the red to the yellow, the CH will never go off. (that’s not strictly correct, it’s just so you understand).

    I presume you have a wireless Tado receiver somewhere.


  • Montage
    Montage ✭✭✭

    You have a Neutral, Live, Live out, Live in, and Switched Live. You only need live to the Yellow to create CH demand (on). Bin the brown wire and make the blue and red safe.

    Presumably you can get the yellow to your Tado receiver.

  • Montage,

    Many thanks for above, but can I confirm the wiring you mean is (L to R in my photo):

    N blue cap safe

    L Red connect to yellow B

    L Brown - bin

    A Brown - bin

    B yellow connect to red L

    I was a little confused as you said live to yellow, then make red safe? Not wishing to harm my boiler - please confirm.

    Kind Regards

  • Many thanks Montage - CH now working along with HW controlled via TADO receiver and app:)

    I was just somewhat dismayed at TADO's installation procedure - fit bridge (tick done), pair thermostat (tick done), remove old boiler controller, fit Tado wireless receiver (tick done) and finally remove old wireless thermostat and reciever to be informed installation not known, we will contact you in a couple of days! Cr*p

    In my humble opinion they should ask for all components that are going to be replaced before installation commences (for non-professionals) so as any non-known parts that will scupper the attempt can be flagged up at the very beginning.

  • Montage
    Montage ✭✭✭

    I can understand that. It’s not fun to be stopped dead and left hanging in that state.

  • Loachee
    edited January 2023

    Hello, Newby here. Similar situation to above but different boiler and V3+ Starter Kit. Followed the App installation instructions to the part about dealing with existing wireless thermostat. Waited for response from Tado who replied saying that Tado is not compatible with my system!

    Boiler is Baxi Duo-Tec combi with the Baxi wireless receiver. The thermostat/transmitter is a standalone thing with a mechanical clock.

    Even the Baxi boiler installation instructions say you can install an external control by removing the link on the terminal block, (yellow), and wiring the new switch across those terminals. But, what do I do with the existing controller? I would assume it needs disconnecting or decommissioning somehow as per other threads I've read, just can't find the instructions for my boiler.

    Can it really be correct that I can't use Tado? Seems hard to believe


  • If you can set it to always on you can probably leave it installed.
  • Hello. I think I have a similar or related question. I have the same BDR91 and have installed the TADO Receiver (see picture). However when I switched the power on, the boiler is on constantly, regardless of what the Thermostat or Receiver does. Any help appreciated. Thank you.

  • UPDATE: I checked some other posts on the boiler always being on and they suggested a stuck relay switch in the Receiver was the cause. As suggested I 'tapped' it with the end of a scredriver and amazingly it's working now. Tado support had already given up and suggested I take the whole Kit back to Screwfix as Tado had sent out a replacement Receiver. It looks like the stuck relay switch was the cause. Hope this helps others with the same problem.