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14.4. Setting the time programmes
The operating principle of the Zehnder Eversky unit is to continuously adjust the airflow rate according to the CO₂ level
measured in the room to be ventilated by acting on the speed of the fans in order to always optimise comfort and energy
consumption.
The time programming is adapted to the type of occupancy of the room, and whether or not the Zehnder Eversky central
unit needs to maintain thermal comfort in that room.
If thermal comfort is to be maintained because there is no room heating/cooling and the Zehnder Eversky unit is
equipped with a heating coil, permanent ventilation with no shut-off times is preferred.
Conversely, if thermal comfort is provided by an existing heating/cooling system and there is no night-time occupancy,
the machine can be switched off during this time if there is no minimum ventilation requirement (e.g. residual moisture
removal, VOCs, etc.). It goes without saying that the absence of ventilation means that the room cannot be heated or
cooled.
The time programming involves associating 2 adjustable ventilation levels (low speed* / normal speed*) with 2
adjustable time slots (period 1 / period 2), for all days of the week, and for the days included in the holiday period.
The holiday period is defined by a start day/month and an end day/month. Up to 24 different periods can be set.
By default, the 1st day of the year is a day that is part of the holiday period.
The time period associated with normal speed does not allow the airflow to be regulated according to the CO₂ level. In
order for the CO₂ regulation to be active, the desired time period must be associated with "low speed".
The low speed should therefore always be programmed at least during the day when the room is occupied, and the rest
of the time if a minimum air exchange is required.
The night cooling function, set as standard to operate between 00:00 and 6:00 (if the activation conditions are met), is
not activated if the unit operates at normal speed during this time slot.
When a low speed time slot and a normal speed time slot overlap, the normal speed time slot has priority over the low
speed time slot.
When the Zehnder Eversky is in normal speed, the fans will run at the speed set in the "Fan control / output 1/1" setting.
Minimum access level: Operator
Access path:
Temperature control
Ventilation control
Time settings
Access rights
Time / Date
Pgr normal speed
Pgr low speed
Forced operation
Normal speed
Monday
Period 1:
00:00 - 00:00
Period 2:
00:00 - 00:00
Precautions regarding the setting of time periods:
00:00 ... 00:00 means that the time period is not set
00:00 ... 24:00 means that the time period extends over the whole day, continuously.
Zehnder Eversky
