Plant diagram
Figure: Example for a heating/chilled ceiling application 2-pipe system
Key:
DXR2… | Automation station |
| R1 | Room operator unit |
Rcg | Ceiling heating/chilled ceiling valve |
| D1 | Presence |
CdnMon | Condensation monitor |
| D2 | Window contact |
Sequences
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Y | Output signal |
| TR | Room temperature |
SpH | Effective heating setpoint |
| SpC | Effective cooling setpoint |
YH | Heating valve |
| YC | Cooling valve |
Chovr | Changeover system |
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Figure: Modulating heating and cooling sequence with changeover system
Changeover system
The central function for chilled water supply determines whether the water system is used for heating or cooling based on heating/cooling demand of individual rooms in this supply group. The evaluated result is sent via grouping to the room segment to enable the heating or cooling sequence in the room.
The changeover determination logic counts each the segments with heating or cooling demand.
The cooling controller is disabled during heating, the heating controller for cooling.