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Siemens Building Technologies
Basic Documentation LMU54... / LMU64...
CC1P7494en
HVAC Products
3 Functions
07.11.2002
Since S / W changeover applies to all connected heating circuits, refer to «S / W
changeover».
•
Automatic shutdown of heating
•
Saving energy without sacrificing comfort
This is a fast-acting savings function since the heating will be switched off as soon as no
more heat is required. This ensures efficient operation throughout the year as there is
no need to switch off the heating manually – a special benefit during intermediate
seasons.
Without room influence
If
no
RU is connected, the room temperature setpoint will
not
be readjusted by the room
influence.
In that case, changeover of the automatic 24-hour heating limit takes place in
accordance with the adjusted setpoints.
The basic values used for the process are those of the composite outside temperature
and those of the current room temperature setpoint.
If the composite outside temperature exceeds the current room temperature setpoint,
the heating will be shut down.
Switch-off point of heating:
TaGem = TRw
If the composite outside temperature drops by more than 2 °C below the current room
temperature setpoint, the heating will be switched on.
Switch-on point of heating:
TaGem = TRw - 2 °C
06:00
22:00
20
15
10
5
0
ON
OFF
TRw
25
TaGem
7494d26/0201
TRw -2 °C
14:00
T
°C
t
H
t
14:00
06:00
22:00
H
Automatic 24-hour heating limit
TaGem
Composite outside temperature
TRw
Room temperature setpoint
During the time the automatic 24-hour heating limit is active, the heating will
automatically be off.
ECO functions
S / W changeover
Automatic 24-hour
heating limit
Benefits
Description
Introduction
Process
Switching off
Switching on
Effect