User Manual
Table Of Contents
- 1 Purpose of this document
- 2 Why is a healthy, productive indoor climate so valuable?
- 3 The role of building automation in health and productivity
- 4 Control applications and targets (CO2, VOC, RH, PM2.5)
- 5 Recommendations for specific building types
- 6 Monitoring indoor climate parameters for health and productivity
- 7 Controlling indoor climate parameters for health and productivity
- 8 Products for a healthy productive indoor climate
- Appendix 1: Indoor air quality (IAQ) – Combined CO2 and VOC sensors
- Appendix 2: Integration of RDF../RDG.. (KNX) in Desigo
- Appendix 3: Other indoor climate parameters – NO2, SO2, O3
- Appendix 4: Tender texts
- External references
- Siemens reference documents
- Glossary
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detector reports occupancy, the room is occupied, and must be controlled to the occupancy
temperature setpoint.
Room equipment
Temperature sensor
This sensor should be wall-mounted and measure the room temperature.
Air quality sensor (Combined CO
2 and VOC)
This sensor should be 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
Supply air volume control
The room must be heated or cooled via a single-duct supply and extract variable air volume
system. Room supply air cascade control must make it possible to reach the required room
temperature very quickly. Based on the measured room temperature, the room temperature
controller must calculate a setpoint for the supply air temperature at the discharge air outlet.
When the room needs cooling, the supply air damper must control the supply air between
min. and max. cooling to maintain the room temperature at the cooling setpoint. The room
temperature must be acquired via a sensor located in the room unit or an extract air sensor in
the duct. The described operating conditions define the various operating modes.
Air quality (combined CO
2/VOC) control
The IAQ room sensor measures the higher value of the CO
2/VOC concentration. If the
measured quality of the indoor air is below the set CO
2/VOC limit, the air quality controller
operates at Vmin. If the measured air quality exceeds the CO
2/VOC limit, the air volume
setpoint will be increased up to Vmax (for a preset value of CO
2/VOC Max). Vmin must be
determined by the lower of the two setpoints for heating and cooling, and Vmax by the
higher of the two setpoints.
Heating valve control (optional)
Sequential control of VAV damper and reheating valve is required to achieve the room
temperature heating setpoint. When the room temperature drops below the heating setpoint,
the reheating coil valve must be opened and the variable air volume (VAV) damper must be
controlled to a position that provides the minimum air volume. After the reheating coil valve
is fully open, the variable air volume (VAV) damper must control the supply air between min.
and max. heating to maintain the room temperature at the heating setpoint.
Cooling valve control (optional)
Sequential control of variable damper and re-cooling valve is required to achieve the room
temperature cooling setpoint. When the room temperature exceeds the cooling setpoint, the
cooling coil valve must be opened and the variable air volume (VAV) damper must be
controlled to a position that provides the minimum air volume. After the cooling coil valve is