Vaillant geoTHERM Operating Instructions Manual page 108

10 Glossary
Target room temperature
The target room temperature is the temperature that you
would like in your apartment and which is specified in your
controller. Your boiler continues to provide heat until the
room temperature is equal to the target room temperature.
The target room temperature serves as a guideline for reg-
ulating the flow temperature according to the heating
curve.
Set values
Set values are desired values that you specify in the con-
troller, e.g. the target room temperature or target tempera-
ture for DHW loading.
Flow temperature
See Heating flow temperature.
DHW loading
The water in the domestic hot water cylinder is heated to
the selected room temp. setpoint by the boiler. If the tem-
perature in the domestic hot water cylinder falls by certain
amount, the water is heated up again to the room temp.
setpoint. You can program time windows for heating up the
contents of the cylinder.
Weather-controlled
The outside temperature is measured by a separate sensor
which is mounted in the open air, and the results are trans-
mitted to the controller. At low outside temperatures, the
controller provides increased heating output; at higher out-
side temperatures the heating output is reduced.
Time windows
Three time windows per day can be programmed for the
heating, DHW loading and the circulation pump.
Example:
Time window 1: Mo 09.00 - 12.00 hrs.
Time window 2: Mo 15.00 - 18.30 hrs.
In the heating, each time window is allocated a target value,
which the heating installation maintains during this time.
For DHW loading, the target hot water temperature prevails
for all time slots.
The time windows specify the operating times for the circu-
lation pump.
In automatic mode, the system is controlled in accordance
with the specified values in the time windows.
Circulation pump
Depending on the length of the pipe, there may be a brief
delay before hot water flows when the hot water tap is
opened. A circulation pump circulates hot water via your
hot water pipe. This ensures that hot water is immediately
available when you turn on the tap. Time windows can be
programmed for the circulation pump.
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Operating instructions geoTHERM 0020051578_03