Room Operating Modes; Description - Siemens Desigo RXB Technical Manual

Comfort
Precomfort
Economy
Protection
Risk of frost limit
Siemens
Building Technologies
5

Room operating modes

5.1

Description

The operating modes in DESIGO RXB are Comfort, Precomfort, Economy and
Protection. In addition, the controller has a frost Protection limit, at which an alarm can
be triggered. Each room operating mode has separately adjustable heating and cooling
sequence setpoints.
Heating
Y [%]
100
0
Y Output signal (valve or damper actuator).
TR Room temperature.
Comfort is the room operating mode in an occupied room. The room temperature is
within the Comfort range. The room controller operates in the heating or cooling
sequence with the resultant Comfort setpoints.
In Precomfort room operating mode (in an unoccupied room), control uses setpoints
that are slightly under the Comfort setpoint for heating and slightly above for cooling.
Comment: Since Standby is used in standardization specifically for boiler standby, we
now use the term Precomfort for the room operating mode.
(Exception: The switching state in the schedule room occupancy is still referred to as
Standby).
If a room is unoccupied for an extended period of time (e.g. night setpoint via
schedules, see pages 35, 47, 57), energy supply to the room can be reduced
significantly. In the Economy room operating mode, control uses setpoints that are
slightly under the Precomfort setpoint for heating and slightly above for cooling.
If the building is unoccupied over an extended period of time (e.g. vacation), the
temperature setpoints can be reduced or raised so that the building and all equipment
are protected against heat or cold at any time.
If the room temperature drops below the risk of frost limit value , an alarm is triggered
that can be further proceeds in the building automation and control system.
The room controller continues to operate at the relevant setpoint (e.g. Protection ,
Economy , etc.).
The alarm value in the controller is set to 5 °C.
RXB (KNX) Applications library
Room operating modes
Cooling
CLC and RAD description of functions for CC-02 CM110384en_03
TR
Comfort
Precomfort
Economy
Protection
Frost risk
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28 Feb 2009