Zehnder ComfoAir 70 Instructions De Montage page 7

Installation of the mounting
block
The location of the ComfoAir 70
must meet all local and national code
requirements. Ensure that proper clearance is
provided to other fixtures in bathrooms or other
"wet" rooms.
The mounting block should be secured in the
wall opening prior to installing the interior and
exterior wall finishes. Only non-expanding
adhesive or low expansion foam may be used
to secure the mounting block in the opening.
After securing the mounting block in the wall
opening, cut the block to length so that it is
flush with both the interior and exterior surfaces
of the structural layer(s) of the wall (framing
or concrete/masonry) - Fig. 3. both the interior
and exterior exposed surfaces of the block
should be covered by the wall finish materials.
Fig. 3 – shortening the EPP block
Only a round opening to match the PVC pipe
diameter should remain in the wall's finish
layers.
Before installing the ventilation unit, the PVC
pipe must be cut to length so that it is flush with
the surface of the façade and the interior wall
(Fig. 4). Seal the gap between the wall opening
and the mounting block with suitable sealant at
both the interior and exterior.
After the installation, reapply the dust covers to
both sides of the PVC pipe.
Fig. 4 – shortening the PVC pipe
Square mounting block
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