Technical data
3.5 Additional functions
The heating / cooling changeover information can be received via bus. This is only
possible if the control sequence is set to automatic heating / cooling changeover
(parameter P01 = 3) and no local input X1, X2, D1 is assigned with this function.
In the absence of the required information (e.g. due to problems with data
communication, power failure, etc.), the thermostat operates in the last valid room
operating mode (heating or cooling).
If a cable temperature sensor (QAH11.1 + ARG86.3) is connected to X1 / X2, and
parameter P38 / P40 is =2, the water temperature acquired by the changeover
sensor is used to change over from heating to cooling mode, or vice versa.
• When the water temperature is above 28 °C (adjustable via parameter P37),
the thermostat changes over to heating mode.
It stays in heating mode until the temperature falls below 16°C (adjustable
viaparameter P36).
• When the water temperature is below 16 °C (P36), the thermostat changes
over to cooling mode.
It stays in cooling mode until the temperature rises above 28°C (P37).
• If the water temperature is between the 2 changeover points immediately after
power-up (inside the hysteresis), the thermostat starts in previous mode.
The water temperature is acquired at 30-second intervals and the operating state is
updated accordingly.
P36
M
T
w
[°C]
P37
3191D124
M
Operating mode
Cooling mode
T
w
Water temperature
Heating mode
The QAH11.1 cable temperature sensor for automatic heating / cooling changeover
can be replaced by an external switch for manual, remote changeover:
3076Z03
X2
M
T
X2
M
QAH11.1
T °C
Contact open heating mode
Contact closed cooling mode
The sensor or switch can be connected to input terminal X2 or X1 or D1 (switch
only), depending on the commissioning of the inputs (P38, P40, P42).
See also section 3.9 "Multifunctional input".
By using an external switch as changeover, the Operating action (via parameters
P39, P41 or P43) cannot be modified.
The assignment is fix: Contact open heating mode
Contact closed cooling mode
Heating / cooling
changeover via bus
KNX
R
Heating/cooling
changeover
Automatic heating /
cooling changeover via
changeover sensor
Changeover switch
Note
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Siemens RDG100KN, RDG160KN Basic documentation CE1P3191en
Building Technologies Functions 2014-05-23