Viessmann Vitodens 100 Connecting hot Water tank

[SUNEKTM]

Hi,
My dad and I have used all day to connect a external water tank to our Viessmann Vitodens 100 Boiler.

For some reason the 2 hoses we have connected to the boiler neither gets hot (i believe 1 should get hot) and we are at a loss.

Is there a configuration to do on the dash, or any things we need to adjust?

 

[ShaunCorbs]

Is it a 4 pipe system? Eg 100 system boiler

 

[townfanjon]

Hoses connected to the boiler doesnt sound good , do you want to post a pic ?