User Manual

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Siemens Synco™ living CE1B2740en
Building Technologies Central apartment unit QAX9x3 13.12.2010
Plant operating mode
The individual rooms can be configured merely for heating/cooling operation,
or for automatic changeover between the two operating modes.
Main menu > Rooms > Room X > Room operating mode > Plant optg mode:
Auto The plant operating mode is changed over automatically based
on room temperature and mixed outside temperature.
(factory setting)
Heating The plant is in heating mode.
Cooling The plant is in cooling mode.
Plants with rooms featuring controllable air conditioners can heat or
cool the rooms independent of each other.
The individual air conditioners are controlled via infrared interface
and a Zennio module (KNX S-mode).
H/C-changeover in Auto plant operating mode
In case of automatic changeover, the central apartment unit checks first the
room temperature and compares it to the average value from the heating
Comfort setpoint and the cooling Comfort setpoint ((H Cw + K Cw) / 2).
If the room temperature is at least 0.5 °C below the average value, heating
mode is released
If the room temperature is at least 0.5 °C above the average value, cooling
mode is released
H Heating mode
K Cooling mode
H Cw Heating Comfort setpoint
K Cw Cooling Comfort setpoint
TR Room temperature
To change over between the plant operating modes heating and cool-
ing, the preset H/C changeover locking time must be expired. This
avoids frequent changeover.
The central apartment unit checks the mixed outside air temperature as a
second criterion and compares it to the outside temperature heating limit and
the outside temperature cooling limit (see page 36).