UK: tado v3+ Vaillant EcoTEC+ System Boiler eBus

plgeek

Hello all.

I recently installed a tado v3+ wireless starter kit (UK version) plus 10x smart TRVs.

The wireless receiver is connected to a Vaillant EcoTEC+ 428 System (not combi) boiler.

Everything is working well, but the system is of course just using on/off relay control.

I would like to now get tado controlled modulation of the boiler to work.

I'm looking for advice on what I need to purchase to make this work, and am getting pretty confused with it all.

My current understanding is that I will need:

1. A Vaillant VR65 controller
2. The EU tado wireless receiver (or the old UK extension kit).

Can anyone in the know with this same/similar setup working comment to help me get my head around this, what I'd need to buy, and how my current working (relay control) wiring would need to change?

Thanks in advance, and happy new year!

plgeek

This is my current plan for wiring (see image):

And to follow the steps helpfully shared by @autolycus in this post:

1. Apply the Vaillant D07 eBus config to the Smart Thermostat as per the instructions at page 12 of https://cdn.brandfolder.io/607DGEMS/as/bxgtx5kghgjrbcs4m68kqch/Extension_Kit_Manual_-_Low_Voltage_Digital_Installations.pdf
2. Connect a 240V L/N/E supply to the Extension Kit. In theory this is not required but I found that the Extension Kit didn't always respond to commands from the app on my phone until I did this.
3. Connect the +/- eBus (low voltage) connections on the Extension Kit to the eBus connection on the VR65. Also connect the eBus on the VR65 to the eBus on the boiler. And connect the cylinder stat and 2 x zone valves to the VR65 as shown in the diagram and photos in my original post above.
4. As per my original post, that allowed me to get HW but not heating. To fix that, I had to do the following...
5. Connect a jumper wire to bridge the two 24 V= RT pins on the boiler circuit board (my boiler came with a jumper for this). Once I did this, the Tado was able to turn on the heating - but only if there was no demand for hot water.
6. Now go into the installer menu on the boiler. On my one, this involves pressing the top two buttons together and then scrolling down to select the installer menu option and providing the passcode (which is 17).
7. Once in the installer menu, scroll through to D70 - Set Diverter Valve Position. By default this is set to 0. Change it to 1 (centre position), as this will allow the boiler (via the VR65) to open both the HW zone valve and the CH zone valve at the same time.
8. Save the setting and exit the menu
   

@autolycus anything I'm missing? Is everything still working well for you?