Installing/Wiring

willocallaghan · January 2020

Hi,

I have brought a Tado smart thermostat and currently attempting to install it.

I currently have a Worcester Greenstar i boiler connected to a Honeywell BDR91 which wirelessly links to a Honeywell EHE0200361. (All images attached)

I have entered this information into the step by step guide on the tado website, however it is telling me that I need to purchase an extension kit from them. I would imagine this is because in most setups, the wireless receiver (BDR91) is hidden away. My receiver is conveniently placed where I would like to mount the tado smart thermostat. I was hoping the wiring would be a simple swap but I've now hit a curveball in that the installation instructions are not helping.

I am likely to be wrong but I was thinking that the wiring would be something like this because the tado is powered by batteries:

BDR91 (N) = TadoST Spare

BDR91 (L) = TadoST Spare

BDR91 (A) = TadoST (COM)

BDR91 (B) = TadoST (NO)

BDR91 (C) = empty

I have attached images of my current wiring and also of the tado smart thermostat terminals. I would really appreciate any advice for wiring the smart thermostat to these cables or if it is true that I need an extension kit.

Thanks very much,

Will