Siemens RDG400 Basic Documentation page 15

External / return air
temperature sensor
Floor heating
Floor heating
limitation function
Recommended values
for P51:
External temp.
Parameter P51
sensor available
OFF No
OFF Yes
10...50˚C No
10...50˚C Yes
Dewpoint monitoring
Siemens
Building Technologies
X2
M
T °C
The sensor or switch can be connected to the input terminal X2 (factory setting) or
X1 or D1 (switch only), depending on the commissioning of the inputs (P38, P40,
P42).
See also section 4.9 "Multifunctional input".
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 or X2.
Inputs X1 or X2 need to be commissioned accordingly. See section 4.9 "Multi-
functional input".
Application "Single duct and radiator" can also be used for floor heating.
The temperature should be limited for two reasons: comfort and protection of the
floor. It is only available with application "Single duct and radiator".
The floor temperature sensor, connected to multifunctional input X1 or X2,
measures the floor temperature. If the temperature exceeds the parameterized limit
(parameter P51), the heating valve is fully closed until the floor temperature drops
to 2K below the parameterized limit.
This function is factory-set to OFF (disabled).
Input X1 or X2 must be commissioned accordingly (P38 or P40 = 1).
See section 4.9 "Multifunctional input".
Living rooms:
up to 26 °C for long term presence, up to 28 °C for short time presence
Bath rooms:
up to 28 °C for long term presence, up to 30 °C for short time presence
The table below shows the relation between parameter, temperature source and
temperature display:
Source for display of room
temperature
Built-in sensor
External temp. sensor
Built-in sensor
Built-in sensor
Dewpoint monitoring is essential to prevent condensation on the cooling coil.
It helps avoid associated damage to the building.
A dewpoint sensor with a potential-free contact is connected to multifunctional input
X1, X2 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.
The condensation symbol
The input must be commissioned accordingly (P38, P40, P42).
See section 4.9 "Multifunctional input".
RDG100, RDG100T, RDG110, RDG140, RDG160 Basic Documentation
Functions
X2
T
M
QAH11.1 3076Z03
Output control according
to
Built-in sensor
External temp. sensor
Built-in sensor
Built-in sensor + limit by
external sensor
is displayed during temporary override.
Contact open heating mode
Contact closed cooling mode
Floor temp. limit
function
Not active
Not active
Not active
Active
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CE1P3182en
28 May 2009