User Manual

Control concept
Desigo room automation
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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 control structure
An HVAC control application in the room is connected to the following:
● HVAC plant in the room via sensors and actuators
● Room coordination application
● Centralized coordination application for HVAC supply chain(s)
● Building operator via BAC workstations
● Building automation and control functions for scheduling
● Room user