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V07-19.0
Figure 12:
Protection against dirt
4
Foundation / erection
Space requirements:
At the location, proper maintenance and the removability of build in components shall be physically
possible. Therefore, a free working space of AHU width + 300 mm shall be available. On the back
site for mounting a 600 mm width passage should remain free.
According to EN 13053 and VDI 3803 it is not permitted, that the bottom of the AHU replaces the
building roof. Furthermore, it is not permitted that the AHU substitutes any part of the building.
4.1
Foundation
Recommended are solid foundations of reinforced concrete, as shown in
foundations, as shown in
right. For strip foundations, concrete or steel beams shall be
bottom-right. Steel beams constructions must have an appropriate stiffness in
relation to the AHU size. The foundation must be flat and leveled, it may not have fall in any direc-
tion or uneven surfaces.
AHUs have to strain via baseframe in longitudinal direction and cross direction optionally in form of
strips or point like the foundation.
Following conditions must be fulfilled:
-
The height difference of the foundation may be
1 mm per meter maximum
. For the entire AHU
length and width a height difference of
5 mm maximum
is acceptable.
-
If the conditions mentioned before are not fulfilled due to uneven foundations or sagging of the
foundation, measures for complying the conditions must be taken (e.g. distance sheets with ap-
propriate thickness).
Attention!
If these structural conditions are not met, this may be the cause of jammed doors and dampers and
other problems with the AHU.
