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Siemens
RDG400KN,RGD405KN Basic documentation
CE1P3192en
Building Technologies
2017-02-17
3076Z03
X2
M
T
X2
M
QAH11.1
T
癈
Contact open
⇓
heating mode
Contact closed
⇓
cooling mode
The sensor or switch can be connected to input X1 or D1 (switch only), depending
on the commissioning of the inputs (P38, P42) (also refer to section 3.8).
∂
Manual heating/cooling changeover means selection via changeover button on
the thermostat by repeatedly pushing the button until the required mode is
shown on the display (automatic changeover takes place via bus or an external
sensor/switch connected to X1 or D1)
∂
If manual heating/cooling changeover is commissioned (P01 = 2), heating/
cooling mode cannot be changed via bus/changeover sensor/switch; it maintains
the last mode as selected locally via the button
The thermostat acquires the room temperature via built-in sensor, external room
temperature sensor (QAA32) or external return air temperature sensor (QAH11.1)
connected to multifunctional input X1.
Input X1 must be commissioned accordingly (see section 3.8).
The floor temperature should be limited for 2 reasons: Comfort and protection of
the floor.
The floor temperature sensor connected to multifunctional input X1 acquires the
floor temperature. If the temperature exceeds the parameterized limit (P51), the
heating valve is fully closed until the floor temperature drops to a level 2 K below
the parameterized limit.
This function is factory-set to OFF (disabled).
Input X1 must be commissioned accordingly (P38 = 1) (see section 3.8).
Living rooms:
Up to 26 °C for long-time presence, up to 28 °C for short-time presence.
Bathrooms:
Up to 28 °C for long-time presence, up to 30 °C for short-time presence.
The table below shows the relation between parameter, temperature source and
temperature display:
Parameter P51
External temp.
sensor available
Source for display of
room temperature
Output control
according to …
Floor temp.
limit function
OFF
No
Built-in sensor
Built-in sensor
Not active
OFF
Yes
External temp. sensor External temp. sensor Not active
10...50 ˚C
No
Built-in sensor
Built-in sensor
Not active
10…50 ˚C
Yes
Built-in sensor
Built-in limit
by external sensor
Active
Dewpoint monitoring is essential to prevent condensation on the chilled ceiling.
It helps avoid associated damage to the building.
A dewpoint sensor with a potential-free contact is connected to multifunctional input
X1 or D1. If there is condensation, the cooling valve is fully closed until no more
condensation is detected, and the cooling output is disabled temporarily.
Manual heating/
cooling changeover
External/return air
temperature sensor
Floor temperature
limitation function
Recommended values
for P51
Dewpoint monitoring
