User Manual

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Air quality sensor (Combined CO2 and VOC)
This sensor should be a wall-mounted and measure CO
2 and VOC levels. Its output signal
should represent the higher of the two measurements.
Presence detector
This sensor should be ceiling-mounted and detect slight movements, such as a person typing
on a keyboard.
Control sequences
Temperature control
The thermostat acquires the room temperature via its built-in sensor and maintains the
setpoint by delivering actuator control commands to the heating and/or cooling equipment.
Outputs are available to control:
• Air damper
• Heating/cooling coil, radiator, electric heater
Air quality (combined CO
2/VOC) control
The thermostat controls the air damper position according to the combined CO
2 and VOC
level acquired by the Air Quality sensor. Since the air damper position is also controlled
according to the temperature, it depends on which is higher, the temperature demand or the
combined CO
2 and VOC level demand signal.
The function shall improve the indoor air quality by increasing the volumetric air flow
or VAV output signal respectively.
• If the IAQ value of the room is below the preset CO
2 setpoint, the VAV output signal
is controlled in accordance with minimum flow
• If the IAQ value exceeds the CO
2 setpoint, the VAV output signal is increased slowly
until maximum flow is reached
• CO
2 control is activated only in Comfort mode. In Economy and Protection mode,
this function is disabled