Boiler: More heating required
It’s an overcast Sunday morning. The cloud cover means that the house doesn’t have any solar energy heating the house through the windows.
In the bathroom, the required temperature matches the actual temperature. In the living room, it is 2 degrees cooler than the required temperature and the bedroom is warmer than the required temperature.
There is a demand for heating so that the living room can be warmed up, meaning that a high flow temperature is required. The boiler needs to get fired up!