5.3
Placing in the excavation and laying the connections
The filter is installed in the prepared excavation and is then connected to the relevant pipes etc. Attention,
it is important to note that all the pipes to be installed must have a gradient of at least 1% in the flow
direction without sagging or bending downward.
Important: DIN 1986 must be followed, therefore the diameter of the supply pipe = the diameter of the
run-off pipe.
5.4
Filling
The filter system is to be placed in the prepared excavation pit in a horizontal position without shocks.
It is essential to check the correct position of the filter system before and during filling. The filter
encasement is manufactured layer by layer with rounded gravel (granulation 8/16 according to DIN 4226-
1) to a width of approx. 300 mm. The individual layers are laid in heights of 300 mm and compacted
afterwards with a light compacting machine (hand rammer). It is essential to avoid damage to the filter
housing during compaction. So that no forces are transmitted to the filter housing, the telescopic dome
shaft cover must be lined accordingly and vibrated in. In the case of areas subject to car or truck traffic,
please note 5.5.2 or 5.5.3 respectively. The cover is subsequently placed in position and locked with a
childproof lock.
5.5
Mounting the telescopic dome shaft cover
The telescopic dome shaft cover allows the stepless adaptation of the filter system to the ground surface.
It is to be made absolutely certain that the inlet is not totally or partly blocked by the telescope in the
finally installed state. It may be necessary to shorten the telescope – this is easily done from below.
Before inserting the telescopic dome shaft cover, the profile seal is inserted into the sealing groove in the
housing. The telescope and the seal must be generously greased with the soft soap supplied (do not use
petroleum-based lubricants).
Attention: If the soft soap dries, the telescopic dome shaft cover can only be moved with great difficulty
and therefore there is a risk of the seal slipping out of the sealing groove. It must be checked before filling
that the seal is seated correctly.
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5.
Installation and assembly
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