I still don't understand how it works. Situation: east-faced room with a big window. The sun shines directly to the room in the morning and falls to the wall opposite to the window. If we apply internal source construction to absorb the heat from the sun, it should help us to avoid overheating. The cooling wall may stay at the temperature of the room - no need to chill the indoor air. So, we apply low temp rad cooling to this wall, make it variable flow with constant temperature, control it by the zone operative temperature thermostat to detect the direct sun. And it does not work. There is some flow, but it's constant. The inside surface temperature is different from User Specified Location temp from radiant cooling outputs (I asked to report the temperature on the inside surface) - why? The cooling rate shows some growth only when the room temperature rises - seems like it tries to calculate cooling rate caused by the temperature difference between the surface and the air, but what about sunlight absorption? Overall it looks like it tries to do something, but it is really unclear what exactly... How would you model this situation and how to make it work?