S&P SLIM Series, Manual, Page: 49 / 72

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21. REMOTE NORMAL SPEED
By closing an external digital contact (see electric diagram), it is possible to force the fan operation at "Normal Speed"
for a setted time. (30 mins. by default)
This function can be activated, only when the unit is not within a timer period of normal speed or extra speed.
If this function is activated while the unit is in an "normal speed" or "extra speed" time period, the counter will start
counting after the time period has expired.
22. REMOTE EXTRA SPEED (not available in COP mode)
By closing an external digital contact (see electric diagram), it is possible to force the fan operation at extra speed for
a setted time. (30 mins. by default)
If this function is activated while the unit is in an "extra speed" time period, the counter will start counting after the time
period has expired.
23. FREE COOLING BY NIGHT
By default, this feature is disabled. To enable it is necessary to accesss to Fan Settings. This function is used during the
summer to cool off buildings during the night by using fresh outdoor air. This allows reducing the need to resort to air
conditioning during the day.
To use the free cooling by night function, the information received from the outdoor probe (fresh air) and from the extract
temperature probe is used. These two probes are present and integrated in the unit.
P K P K
As you can see above, some of the start conditions can be modified. By default, the conditions for free-cooling activation
to occur are as follows. (ALL the conditions must be satisfi ed):
Start conditions:
• Less than 4 days have elapsed since the last start of the installation.
• The outdoor temperature during the previous operation period exceeded the force limit of 22°C.
• It is between midnight 0:00 am and 7:00 am in the morning.
• The timer outputs for “Normal flow”, and “Extra flow” are off.
• The “Remote Normal Speed" is not activated (external switch).
• The unit is not remotely stoped by means of the external switch” (see section "20. REMOTE ON/OFF").
• A time program will be activated (“Start”) within the next 24 h.
Once activated, it runs for 3 minutes to make sure that the temperature measurements are representative (by creating
air movement in the ducts). After three minutes, the controller checks the stop conditions:
Stop conditions:
• The outdoor temperature is above 18°C or below 10°C (risk of condensation).
• The extract temperature is less than the stop value (18°C).
• The time programs for the “Normal flow” or “Extra flow” are set to “Start”.
• The “Remote Normal speed" is activated (external switch).
• The unit is remotely switched off by means of the external switch (see section "20. REMOTE ON/OFF").
• It is later than 7:00 am in the morning.
If at least one of these conditions is satisfied after the first three minutes of operation, then the unit is stopped again.
When the free cooling function is active, the fans run at the speed of the fans is set depending on the selected mode:
• Fans in CAV mode: Normal airfl ow + Offset.
• Fans in COV mode: Normal pr Offset.
• Fans in VAV auto: Airfl ow corresponding to the CO2 level + Offset.
• Fans in VAV manual: Freecooling is not compatible with this mode.