CLIVET ELFOFresh2 CPAN-U 70-120 Series, Technical Bulletin

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16 ELFOFresh² BT15B012GB-00
Flow modulation
The new fans in direct current gave saving 60% for the absorbed capacity
The energetic consumption for the ventilation represents the main cost for the fresh air units.
In order to reduce the operating costs and obtain the highest energy saving,
all units have high-efficiency fans with electric control in
direct current: an energy saving 60% than traditional fans is guaranteed.
The electronic control the automatic modulation of the air flow that, according to the requirements, can increase, in case of FREE-COOLING,
or decrease for the dehumidification, extending the functional limits, and limiting the optional use of modular electric heaters from 0,7 or
3 kW
(optional) only for exceptional situations.
The unit is configurated for 40 Pa available head; by changing some parameters it is possible to reach up to
120 Pa
.
The air flow reduction guarantees the comfort during winter operation
In correspondence to the low temperature values of the fresh air (lower than – 5°C), the intake temperature is fixed (I), approximately equal
to the indoor air (20°C) using the air flow reduction (A).
This reduction is performed in order to avoid the intake of fresh air in the rooms that might cause the risk of uncomfortable cold draughts.
In this conditions, the active thermodynamic recovery can completely satisfy the ventilation load.
Nominal air flow operating: fulfill of the building load in addition of the ventilation
In the range of fresh air temperature between – 5 °C and + 20 °C,
the fresh air flow rate keeps constant (B): the intake temperature
in the room (II) increases as the fresh air temperature increases;
ELFOFresh
2
, besides compensating the ventilation dispersions, is
able to fulfil, either completely or partially, the building load for
heating of building.
Increase of air flow rate for cooling the rooms in middle season
In the range b 20 °C and + 25 °C the building might need
being cooled, though without relevant need, it is also possible
to perform the free-cooling, by simply allowing a higher air flow
rate into the rooms and leaving the compressor deactivated (C).
In this case, the efficiency is defined as the ratio between the
cooling capacity delivered to the room by the fresh air (directly
proportional to the temperature difference between outdoor
and indoor, according to the fresh air flow rate) and the absorbed
electric capacity (in such case, only by the fans). Due to the reduced
absorption of the fans, it is possible to reach a very high efficiency
in this operating condition. The intake temperature in the room is
exactly equal to the outside one (III).
Reducing the air flow rate to dehumidify
For a more efficient dehumidification of the fresh air, ELFOFresh
2
reduces the flow rate by modulating the fan speed (D); in this way, it is
possible to cool the rooms by using radiant panels with a subsequent efficient dehumidification.