Thanks both, the only way seemed to get some improvement was swapping the blue to channel 4 and the yellow bit to 2. But boiler heats up then but nothing to radiators.
Will check if valves open as suggested
So I swapped the little yellow tab round on that tado, swapped wires and the boiler clocked the CH to heat but then not sending it round to radiators. Time to call in the professionals, thank you for help