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ENGLISH
8.8 Override
A digital entry makes it possible to
override the operation of the unit
in a normal regime. The override
period is adjustable; the timeout is
adjusted from the factory at 0s to
be compatible with our presence
detection systems and our control
buttons.
Terminal blocks are available in the
terminal cabinet (use of a potential-
free contact).
Time in ext. Running
Extended: 0 min
Time settings
Extended
running
Extended running
0 min
8.9 Night-time Free Cooling
This function is used during summer to cool buildings at night, using external fresh air. This reduces the
need to use air conditioning during the day.
To use the free cooling function, the controller will use the information stemming from the fresh air temper-
ature sensor and the return or room temperature sensor.
The free cooling is only eff ective if start-up conditions are met.
Start-up conditions:
• Fewer than 4 days have elapsed since the the installation was last started up.
• The outdoor temperature during the previous operating period surpassed the pre-adjusted limit of
22°C
(1)
.
• It is between 12:00 a.m.
(1)
and 7:00 a.m.
(1)
.
• The time programmes for high speed, the manual start-up in high speed and the external control are
on "Stop".
• A time programme will be activated ("Start") during the next 24 hours.
If ALL the conditions are met, the free cooling begins. It continues for 3 minutes to make sure that the tem-
perature measurements are representative (by the creation of an air movement in the ducts).
After three minutes, the controller verifi es the stop conditions.
Stop conditions:
• The exterior temperature is above 18°C
(1)
or below 10°C
(1)
(condensation risk).
• The return temperature is below the stop value (18 °C).
• The time programmes (timer) for normal speed, normal override and external control are on "Start".
• It is after 7:00 a.m.
(1)
.
If at least one of these conditions is met after the fi rst three minutes of operation, the installation is then
stopped again.
When the free cooling function is active, the fan resorts to maximum speed (this speed can be reduced
by confi guration), and the coil/electric heater control outputs are cut. The heating output continues to be
blocked for 60 minutes (1) after the function has ended.
(1)
The default values can be altered by confi guration in "expert mode".
Particular conditions of use of the night-time free cooling in constant pressure mode (COP)
In constant pressure mode (COP) during the night, the fl ow modulation dampers of the various zones can
be in a closed position, or adjusted to the minimum fl ow. To take advantage of night-time free cooling, the
opening of these dampers must be forced to allow the free cooling fl ow to pass through. We recommend
the use of a power connector cabinet for the purpose of CAPI relay.