Basic Documentation

Functions
Additional functions
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● An external switch is connected to B1/X1/X2 (P38/P40 = 9) to change
heating/cooling mode remotely.
● Manual heating/cooling changeover means selection via changeover button on
the thermostat by repeatedly pushing the button until the required mode is
displayed (automatic changeover via external sensor / switch connected to
B1/X1/X2).
● If manual heating/cooling changeover is commissioned (P01 = 2),
heating/cooling mode cannot be changed via bus/changeover sensor/switch; it
remains in the last mode selected locally via button.
The thermostat acquires the room temperature via built-in sensor, external room
temperature sensor (QAA32), or external return air temperature sensor (QAH11.1
or QAP1030/UFH) connected to multifunctional input B1/X1/X2.
Inputs B1/X1/X2 must be commissioned accordingly. See Multifunctional input,
digital input [➙ 43].
4.5.2 Hotel keycard/Presence detector
The operating mode can be changed to Comfort or Economy based on room
occupancy (room occupied or unoccupied, via presence detector or hotel keycard).
The presence detector or hotel keycard input switches the operating mode to
Comfort when the room is occupied and switches back to the previous operating
mode when the room is unoccupied.
Presence detection or hotel keycard is also possible via bus. In this case, do not
assign the function to local input S1/X1/X2.
4.5.3 Output functions
The changeover sensor ensures changeover between heating and cooling based
on the acquired water temperature. We recommend activating 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 opened for 1 to 5 minutes (adjustable) at 2-hour intervals during off hours.
The function is valid for outputs On/Off and all applications.
CAUTION! The Purge function (P50) must be disabled if the thermostat is
used in compressor-based applications.
Limit the On/Off switching cycle to protect HVAC equipment, e.g., the compressor,
and to reduce wear and tear. The minimum output on time and off time for the 2-
position control output can be adjusted from 1 to 20 minutes via P48 and P49. The
factory setting is 1 minute.
Readjusting the setpoint or heating/cooling mode changeover immediately results
in output state calculation; the outputs may not hold the minimum 1-minute On/Off
time.
If P48 or P49 is set to greater than 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.
Floor heating/Floor
cooling
Manual heating/cooling
changeover (P01)
External/return air
temperature sensor
(P38/P40)
Purge function (P50)
Minimum output On/Off
time (P48, P49)