CLIVET ELFOFresh2 CPAN-U 70-120 Series, Технический бюллетень

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BT15B012GB-00 ELFOFresh² 41
Definition of the room’s distribution system
The air distribution in ELFOAir is a “manifold” system and therefore consists of one or more distribution
boxes (manifolds) where flexible hoses are “attached” to it to supply the openings/grilles of the ventilation
system.
This kind of solution offers 2 great advantages:
•
using a single duct in terms of diameter, facilitating installation considerably
•
avoid noise migration from one room to another through the ducting
There are two available distribution boxes: the first has 8 fittings (4 on each side) and the second features
14 fittings (8 on the front and 6 on the side).
The choice of the box depends on the number of ducts required, the position of the duct connections on
the distribution box based on the available spaces and maximum airflow.
To ensure optimally balanced distribution, it is preferable to install the distribution boxes in a central position in relation to the outlets that supply openings
(see the figure to the side).
Air flow adjustment for each outlet is provided by calibrating the control system present in each specific outlet except for the rectangular grilles (GIVEX and
GINOX) where you must use a separate flow regulator (REPPX) to be placed at the entrance to the flat tube.
Flexible ducts that are used by the ELFOAir system from the distribution box to the outlets can be of two types:
•
TFT90X round flexible tube with DN90 outer diameter and inner diameter of
78 mm, suitable for a maximum flow rate of 60m
3
/h (v = 3.48 m/s). For higher
flow rates, only for the square grille (GQIEX) or the valve (VIEX), you can use
two ducts on the same line thanks to the A90DPX adapter. The round flexible
tube must be insulated with a special IT90X isolation, since, under certain
transitional conditions, the supply flow temperature could cause condensate
build-up.
•
TFPNX flat flexible tube with 52 mm height and 132 mm width (section
0.0041m
2
), suitable for a maximum airflow rate of 50m
3
/h (v = 3.38 m/s). For
higher flow rates, only for the square grille (GQIEX) and the valve (VIEX), you
can use two ducts on the same line thanks to the A90DPX adapter. The flat
flexible tube must be insulated with a special IT100X isolation, since, under
certain transitional conditions, the supply flow temperature could cause
condensate build-up.
Both the tubes can be ceiling-mounted or buried in the screed as their mechanical characteristics afford resistance to crushing. The flat tube dimensions
allow a reduction in the thickness of the screed, as shown in the drawing.
The length of each duct is determined based on the route that connects the box to the grille.
If the path from the distribution box to the inlet involves bends in tight spaces, the use of one or more stamped elbows will be required.
Since the pressure drops with each bend are significant, it is a good idea to try to avoid their use whenever possible.
Inspection of the system’s pressure drops
Once the layout for distribution has been determined it is necessary to make
sure that the pressure drops in the supply and extraction sections do not
exceed the maximum available pressure of the ELFOFresh
2
fresh air unit.
When checking the distribution system, take into account all of the elements
that cause pressure drops.
For the supply section: fresh air intake grille, fresh air ducts, pre-heating heater
(if any), ducts to the distribution box, humidifier (if present), flexible extraction
ducts, outlets/grilles for supply and generated pressure drops for balancing
the system through the integrated control system in the outlets or through the
flow rate controllers (only for rectangular GIVEX and GINOX grilles).
For the extraction section: fresh air exhaust grille, fresh outdoor air ducts,
return air filter, ducts to the distribution box, humidifier (if present), flexible
extraction ducts and outlets/grilles for extraction and generated pressure
drops for balancing the system through the integrated control system in the
outlets or through the flow rate controllers (only for rectangular GIVEX and
GINOX grilles).
Note: the use of the electrostatic FES filter in place of the standard folded FAS filter allows you to reduce considerably the pressure drops in the supply
section and therefore save energy on ventilation.
The pressure drops of each single part vary in relation to the air flow, while the pressure drops of the ducting also change depending on the length of the
duct.
In the next “accessory section” are shown the pressure drops of each element of the system ELFOAir.
Since ELFOAir, a system of distribution manifolds, the analysis of total pressure drops is greatly simplified.
The pressure drops that the ELFOFresh
2
must win downstream of each box of distribution coincide with the loss of load higher among all those of the
individual ducts to it connected.