Trouble connecting new Tado Wireless receiver to new boiler.

I've had to get a new boiler - Vallant ecoFIT pure 825-835. The existing wireless receiver did'nt seem to be working, so decided to get a Tado wireless kit.

The problem is that the heating engineer can work out how to wire the Tado unit in toe boiler PCB. I've

I have looked on line and cannot find anything similar.

Where are the corresponding blue and brown wires that are in CH COM & CH NO supposed to fit in the connector?



  • CH COM and CH NO are standard connections, even on the old dumb mechanical thermostats. Are you sure your heating engineer is qualified?

  • I’m comfortable with the wiring of the wireless unit (ch com ch no), what we / I can’t figure out is where in the boiler PCB do the wires from ch com & ch no go. The PCB doesn’t look like the images I’ve seen on line.