Vaillant ecotec plus and ebus

Hi there.
I've recently had a Vaillant ecotec plus 835 boiler fitted. I've also just bought a tado v3+ wireless starter kit.
Just going through the installation instructions on the app and it says to wire the wireless receiver to 24v=RT on the boiler. Is this correct as I thought it should be wired to - /+bus for boiler modulation.
Any help would be greatly appreciated

Best Answers

  • Kissarmy
    Kissarmy ✭✭
    Answer ✓
    Unfortunately Tado removed ebus connections from UK wireless receivers. I too was caught out by this but managed to buy an old wireless extension kit which did ebus. Tado have relented on this by selling the EU version on their UK installers website. The EU version does not do hot water. no good for UK system boilers, but as you have a Combi it would work for you. Either return your current starter kit for a refund and order a wireless starter kit for combos from Tado or just buy the wireless receiver for combos. The receiver is currently out of stock but the kit for combos is in stock.
  • johnnyp78
    johnnyp78 ✭✭✭
    Answer ✓
    If you ordered this they’ve sent you the wrong version.


  • It is the wireless receiver for combi's that I have. Bought directly from tado last week.
  • What boiler type did you specify when following the installation instructions. I had a few hiccups to start off with. Had to go way down the list to select 'ecoTEC plus 800 series (Combi)' after that I had no problems.
  • I specified ecotec plus 800 series with timeswitch 150
  • 24v sounds like a low voltage terminal which could be used for digital connections. Are there + and - terminals as well?
  • @johnnyp78 Vaillant ecoTEC boilers have terminals for both 230volt AC room thermostats and 24volt DC room thermostats. There are separate +/- Bus terminals.
  • In that case I don’t see any reason why you wouldn’t use the bus terminals. Maybe the app is giving instructions for a low voltage relay connection.
  • I don't see a bus connection on my receiver.

  • My boiler connections

  • @Bigalfie71 that’s the uk version of the wireless receiver. You need the eu version if you want digital connections.
  • Ok thanks, looks like i'll need to send it back.

    Thanks for all your help.