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Comfort is not just derived from having the right kind of air temperature in a room. The temperature of all the surfaces which encompass the room is just as important. The physiologically perceived temperature approximately corresponds to the arithmetical mean of the two.
People feel comfortable when the basic equation of “thermal comfort” is met:
heat generation = heat emission
The important factor is that the heat which is emitted by the human body can radiate as uniformly as possible in all directions. If too much heat is withdrawn on one side (cold spots), we perceive this as unpleasant.

Diagram right
The lower the air temperature in the room (vertical values) is, the warmer the encompassing surfaces (walls, floor, ceiling, together with window and door surfaces) have to be in order to create a cosy atmosphere.

The unfavourable influence of the cold exterior walls and windows (temperature exchange with the body) is for the most part neutralised by locating panel heating in outward facing walls, in particular under windows.

The room temperature can be set lower than is the case with convection heating, because the radiated warmth raises the temperature perceived by the occupant of the room, which means that the feeling of comfort is not affected.

Diagram left
Where there are drafts, both heating costs and discomfort increase. The vertical axis shows the air speed (m/s), while the horizontal axis indicates the room air temperature (°C).

Diagram right
For a pleasant ambient climate the humidity (vertical axis, indicated in %) must be in the median area. The air temperature also influences our perception of moisture.

Room heating systems provide warmth in two basic ways:
By convection and by radiation.
The way in which the warmth is transmitted depends very much on the room heating system.
Diagram below:
And so - the wall provides the most comfortable warmth

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