Radiation-heating
Because we work with pure radiation heating, temperatures of 16°C to 18°C are quite sufficient to give you an agreeable warm feeling. You can compare this with a skier who can sunbathe in a bathing suit at high altitudes and this at temperatures round about freezing point. The radiation effect is especially economical when there are high ceilings or ridges. When the system is in use, we have a surface temperature of 35°C at the inner windowpane. Whereas the room temperature is getting lower, we have a radiation-heating coming from the windowpane into the room.
How they heat
While in convection heating, a heating body is used to heat up air, which then distributes—transfers—heat as it flows over the surfaces of the objects to be heated (walls, furniture, etc.), a radiant panel distributes heat mainly by radiating it.
Thus, when the flow of radiated heat hits objects (like walls, the floor, or furniture), while a small part is reflected (appx. 15%), the majority (appx. 85%) is absorbed by the objects encountered. At this point in the process, radiated energy turns into heat energy (the objects heat up) and as the objects are hotter than the surrounding air, heat is transmitted by convection—the air is heated by the objects.