Siemens RDF800KN Series User Manual

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Siemens RDF800KN.., RDF800KN/VB, RDD810KN/NF Basic documentation CE1P3174en
Smart Infrastructure 2020-02-21
If manual heating/cooling changeover is set (P01 = 2), heating/cooling mode
cannot be changed using the bus, changeover sensor or switch; it will remain in the
manually selected mode.
The thermostat acquires the room temperature through its built-in sensor, external
room temperature sensor (QAA32), or external return air temperature sensor
(QAH11.1) connected to multifunctional input X1 or X2. Input X1 or X2 must be
configured accordingly.
See section 3.9.
The changeover sensor ensures changeover from heating to cooling and vice
versa, based on the acquired water temperature. We recommend you activate the
"Purge" function (P50) with 2-port valves. This function ensures correct acquisition
of the medium temperature even if the 2-port valve is closed for an extended
period of time. The valve is then opened for 1 to 5 minutes (adjustable) at 2-hour
intervals during off hours.
The "Purge" function (P50) must be disabled if the thermostat is used in
compressor-based applications.
In very warm and humid climates, the fan can be run periodically or continuously at
a low fan speed (e.g. in empty apartments or shops) in Economy mode by setting
P61, in order to avoid damage from moisture due to lack of air circulation. See also
section 3.8.
Limit the On/Off switching cycle to protect the HVAC equipment (e.g. a
compressor) and to reduce wear and tear. The minimum output ON-time and OFF-
time for 2-position control output can be adjusted from 1 to 20 minutes using P48
and P49.
The factory setting is 1 minute.
Readjusting the setpoint or heating/cooling mode changeover immediately results
in calculation of the output state; the outputs may not hold the minimum 1-minute
On/Off time.
If P48 or P49 is set to above 1 minute, the minimum On/Off time for the control
output is maintained as set, even if the setpoint or changeover mode is readjusted.
All heating sequences can also be used for floor heating.
You can use fan coil unit heating/cooling sequences for floor heating or cooling by
disabling the fan via P52.
The floor temperature should be limited for two reasons: Comfort and protection of
the floor.
The floor temperature sensor, connected to multifunctional input X1 or X2, acquires
the floor temperature. If it 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.
Factory setting of this function is “OFF” (disabled).
Input X1 or X2 must be configured accordingly (P38 or P40 = 1).
See section 3.9.
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.
Manual heating/
cooling
changeover
External/return air
temperature sensor
Purge function
Caution
Avoid damage from
moisture
Minimum output
ON
-
time/
OFF
-
time
Floor heating/
Floor cooling
Floor temperature
limitation function
Recommended values
for P51:

Siemens RDF800KN Series Specifications

General

Brand	Siemens
Model	RDF800KN Series
Category	Thermostat
Language	English