Boiler or Tado Not Working

[Lamentable]

When I try to turn on the heating in the Tado sadly nothing heats up.

Not sure if my problem is with Tado or the boiler as the hot water works fine.

There is a sound of a relay clicking inside the Tado control unit, but as Tado doesn't always respond immediately to heat demand it's hard to correlate the clicks with the requests made on the app.

Anyway I opened up the control unit and found this wiring which would have been completed by the boiler installer.

When checking the Tado installation options, there is no option at all that corresponds to wiring I have.

The only 4 wire configuration doesn't even match the wiring I have

I would guess that this option is very important as it tells the Tado unit which relays to actuate to turn on the heating.

Given this has worked for a couple of years without any issue, the problem is either:

a) with the boiler itself

b) tado have pushed out an update and invalidated my installation

To prove this, which two wires could I connect to close the circuit and ask the boiler to heat the radiators ?

Thanks in advance.

 

[Lamentable]

Now I am totally confused. I checked the WB system and it says this is a switched live boiler (which is what I expected), however the Tado extension kit has been set to potential free according to jumper position.

I put the grey and black wires in a connector block and the boiler works perfectly.

 

[Lamentable]

Ok, so the wiring is correct.
Potential free means the voltage is not provided by tado to the relay.
I'll bell the unit out tomorrow to see if it behaves as expected.
Despite wrong findings and assumptions I won't delete this in case it's useful to someone in the future.