Will the indoor temperature rise when the radiator is blown by an electric fan?
I think so, too, and even if the heating temperature is stable, we can't ignore the conservation of energy, because there is wind that can produce airflow. This will make the temperature uniform, and the temperature in the upper part of the room will not be higher because of thermal expansion and cold contraction. In this way, the fully distributed temperature will increase the room temperature from the illusion.