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Preliminary 003
Access V4.X Configuration manual
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2019-05-13
Configuration > Functions > Function activation > Heating/Cooling sequences > Recirculation 2
> CO2 control > CO2 sequence 2
If just supply air fan is used for recirculating mixed air, the extract air fan should be slowed down to keep
balance of fresh and exhaust air flows.
Configuration > Functions > Fan control > Extract air fan slaved by exchanger supply air flow >
“Yes”
Parameters of flow calculation through the exchanger then can be adjusted
Configuration > Functions > Fan control > Flow calculation exchanger supply air >
The setpoint of acceptable CO2 level can be set
Data & Settings > Demand Control > CO2 Control > Setpoint mixing damper >
The PID parameters of the CO2 controller can also be adjusted
Configuration > PID controllers > CO2
2.6 Enthalpy control
Measures and compares the energy content (enthalpy) of the outdoor air and the extract air
(temperature and air humidity). When this function is active, the mixing damper signal will be
overridden to recirculation if the enthalpy is higher outdoors than indoors.
Calculating the enthalpy means to calculate the energy content of the air, taking into consideration both
the temperature and the air humidity. The value is given in energy per kilogram air (kJ/kg). If enthalpy
control is configured, enthalpy is calculated both outdoors and for the extract air. If the enthalpy is
higher outdoors than in the extract air, the recirculation damper function will be overridden to increase
the recirculation. The function is not active when using free cooling, in which case outdoor air is used for
cooling the room instead. For the enthalpy calculation to be made the functions enthalpy control and
cooling recovery must be active.
2.7 Dampers
Used dampers can be selected
Configuration > Functions > Function activation > Damper >
If Extract air damper is used instead of Exhaust air or if they both are used in combination, the settings
for flowchart can be changed
Configuration > Functions > Flow chart setup >
2.8 I/O allocation settings
I/O allocation settings show only sensors/signals that are activated in configuration. The allocation of
inputs and outputs defines the routes for data exchange between controller and connected devices.
Configuration > I/O allocation settings >
The actual devices (sensors, fans, transmitters, switches, pumps etc.) that are not connected over
internal bus line should be hardwi
red directly to the controller‘s or expansion unit‘
s ternimals.