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INSTALLATION OPERATIONS AND MAINTENANCE MANUAL - VORT NRG MEGA-R SERIES
7. OPERATING MODE
7.1 Winter operating mode
The return air from the room, with a higher thermal
load than the fresh air, crosses the rotary wheel
exchanger, where it gives up part of its thermal load
and cools down before being exhausted. The fresh air,
with a lower thermal load than the return one from
the room, crosses the heat exchanger in the opposite
direction and heats up before the introduction into
the room. The modulation of the airflow rate, through
variation of the rotation speed of the EC fans, will allow
a precise control of the supply air temperature. During
winter operation, in particular working conditions with
low external temperatures, the heat exchanger could be subject to the formation of surface frost with consequent loss of efficiency.
To prevent this from happening, the unit provides for the controlled management of an automatic defrosting cycle, obtained
automatically by temporarily stopping the rotation movement of the rotary wheel until it is completely defrosted.
7.2 Summer operating mode
The return air from the room, with a lower thermal load
than the fresh air, crosses the rotary wheel exchanger,
where it takes part of its thermal load and heats up
before being exhausted. The fresh air, with a higher
thermal load than the room air, crosses heat exchanger
in the opposite direction and cools down before the
introduction into the room.
The modulation of the airflow rate, by varying the
rotation speed of the EC fans, will allow a precise
control of the supply air temperature.
7.3 Free-Cooling operating mode
When the outdoor air temperature is lower than the
temperature of the room to be air-conditioned and if
the latter requires cooling, the unit operates in Free-
Cooling mode by stopping the rotation movement of
the rotary wheel.
