User Manual

11
Siemens Datasheet A6V10889950_i
Smart Infrastructure 2020-01-14
Operation
Temperature control
The thermostat acquires the room temperature via its built-in sensor and maintains the
setpoint by delivering 2-position valve control commands.
The switching differential is 1 K in heating mode and 1 K in cooling mode (adjustable via
parameters P30 and P31).
Display
The display shows the current room temperature or the setpoint of the current operating
mode (adjustable via parameter P06). Factory setting is to display the current room
temperature.
The heating symbol or the cooling symbol indicates the selected control sequence.
The triangle symbol indicates the relay output connected to the fan coil unit is energized.
Setpoint adjustment and limitations
The factory setting for the Comfort basic setpoint is 21 ℃. The Comfort setpoint can be
adjusted via the +/- buttons. For comfort or energy saving purposes, the setpoint setting
range is limited to minimum (P09) and maximum (P10).
P09<P10 (comfort concept)
If the minimum setpoint (P09) is set lower than the maximum setpoint (P10), both heating
and cooling setpoints are adjustable between these two limits. The customer sets the
desired setpoint and the thermostat controls the room temperature accordingly.
For 4-pipe applications, the selected Comfort setpoint is in the middle of the deadzone (P33).
The unit stops to energize the heating/cooling outputs as soon as the room temperature
reaches the deadzone.
Example Cooling setpoint adjustable: 18…25 ℃
Heating setpoint adjustable: 18…25 ℃
P09≥P10 (energy saving concept)
If the minimum limit P09 is set higher that maximum limit P10, then:
● The setting range of cooling setpoint is P09…40 ℃ in place of 5…40 ℃.
● The setting range of heating setpoint is 5 ℃…P10 in place of 5…40 ℃.
As a result, the maximum heating setpoint and the minimum cooling setpoint can be limited,
thus saving energy and lowering costs.
For 4-pipe applications:
The thermostat runs with the setpoint of the active sequence:
● In heating mode, the heating setpoint is active and adjustable via buttons.
● In cooling mode, the cooling setpoint is active and adjustable via buttons.
Switching from heating to cooling setpoint and vice-versa occurs when the room temperature
reaches the adjusted limitation (P09 or P10) of the inactive sequence. e.g. the thermostat is
in heating sequence and runs on the heating setpoint. When the room temperature reaches
P09, the thermostat switches to cooling mode and runs on the cooling setpoint, provided the
room temperature does not drop below P10.
Example
Cooling setpoint adjustable: 25…40 ℃
Heating setpoint adjustable: 5…21 ℃