Wall heaters are being used more and more frequently. Conventionally, the wall heating is mounted in the outer wall. What should be noted here, you can read here.
Wall heating modern but not always suitable
There have been significant changes in heating technology in recent years. In particular, the wall heating is due to its high potential savings more and more often in focus.
The wall heating should be installed for different reasons, preferably in the outer wall, but this can again lead to disadvantages. What has to be considered with a wall heating in the outer wall, we have discussed below for you.
Functional principle of wall heating
In contrast to most heaters (radiators with hot water supply), heating is based on a different physical principle. Conventional radiators heat the air, which is why they are also known as convection heaters. Wall heaters, on the other hand, rely on the principle of radiant heat. It is not the air, but the illuminated body is heated. As bring various advantages:
- less dust uplift (for asthmatics and allergy sufferers)
- more pleasant and comfortable heat
- if properly used significantly lower heating costs
energy saving potential in principle
A room can be heated to 18 degrees thanks to the radiant heat, but people feel it Temperatures like 21 degrees. In addition, per degree of further heating of the room air via a convection heating the additional effort of energy is six to seven percent.
The path of heat with wall heating in the inner or outer wall
But there are also disadvantages from the technically necessary construction. So the wall heater should preferably be laid in he outer wall. This also has very simple physical reasons. In particular, the facts that cold air sinks and warm air rises, should be noted.
Suppose the wall heater were in the interior wall. Then the warm air would take the following "path": the warm air rises in the room. In doing so, it inevitably moves to the coldest wall, as it creates a strong downward flow. Because the warm air is cooled down on the coldest wall. In an old building without contemporary insulation, the U-value of the wall can be extremely disadvantageous.
This will cool the air even faster and stronger. At the same time the cold air on the floor is sucked in again in the area of the wall heating, since here the warm air rises upwards. In the foot and leg area, therefore, results in a permanent cold draft, which can be extremely unpleasant. Therefore, the wall heater should preferably be mounted on the outer wall.
The thermal insulation of the outer wall is decisive
Here, efficiency and thus potential energy savings result from the thermal insulation. Especially behind the wall heating a very good thermal insulation has to be mounted. Thicker plaster before wall heating is not recommended. Although these would store the heat well, but the heating is significantly slower in the effect.
In case of poor external insulation, a lot of heat is emitted to the outside. Therefore, the flow temperature must be increased, which is reflected again in higher heating costs. Therefore, the wall heating in the old building without appropriate insulation is disadvantageous accordingly.
Consider further factors in the wall heating in the outer wall
In principle, the interior walls could be avoided. But then arises especially in uninsulated, very cold outer walls, the problem of constantly cold feet. But another aspect is important.
The window area must also be taken into account or deducted from the possible area for wall heating, especially for an exterior wall. However, due to the used radiant heat, the design of the wall heating must be correspondingly large area.Tips & Tricks Wall heating in old buildings is particularly rewarding if it is appropriately insulated. As already stated, the insulation should be behind the wall heating in the outer wall or right outside the façade as a thermal insulation composite system (ETICS).