Tado shows as heating but Vaillant ecoTEC plus 831 does not heat CH
We're having some issues with our tado not heating the house.
We have a standard Vaillant ecoTEC plus 831 combi boiler.
The hot water seems fine (adjusting the hot water temperature in the app changes the temperature from the tap), but the central heating shows its heating but the boiler just kicks in for a short time, then the display shows a flashing radiator symbol, which apparently means the target CH water temp has been reached and the pump is still just circulating.
Does anyone have any thoughts - is there a way to adjust the target central heating water temperature via tado?