User Manual

Control concept
Desigo room automation
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HVAC room control
HVAC plants and their HVAC devices in the room influence the climate in
closed rooms.
HVAC plants in rooms are used to:
● Maintain a temperature range suitable for building occupancy
● Control other control variables such as humidity and air quality
● Efficiently operate HVAC plants in the room
HVAC plants in the room are grouped into plant families, radiators (right), Fan
coil units (center), VAV (left), differentiated by mechanical design and
functioning:
The members of the related HVAC family differ only marginally:
HVAC plants in a room consume energy. The supply chains outside the room
supply air, water, or electricity to the room. Linked existing energy sources and
consumers are called supply chain. An air supply chain or a water supply chain
thus is an HVAC system with a supply/consumer relationship to the HVAC plant
in the room.
The supply equipment typically supplies more than one room, and the HVAC
plant in the room often is a consumer of multiple supply chains.
HVAC control basically has the same objectives as the entire HVAC plant:
● Maintain the room temperature in the selected comfort range
● Adapt the room temperature range to room user needs
● Supply, extract, and recirculated air to satisfy air quality and comfort needs
● Adapt the air flows to room user needs
Energy saving requirements:
● Devices for sequential control of a heating and cooling sequence and thus:
– Preventing sequence overlap (simultaneous heating and cooling)
– Using the most efficient energy source
● Reducing the temperature as soon as comfort mode no longer is needed
● Reducing ventilation as soon as it is no longer needed
Coordination of the HVAC supply chain:
● Operation of supply chain equipment as per user demand
● Optimization of operating levels (temperature, pressure) of the supply plant
● Prevention of damages to HVAC equipment
HVAC supply chain
requirements