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Siemens
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CE1P3076.en
Smart Infrastructure
2020-02-21
Fan operation can be limited to be active only in cooling or heating mode, or even
totally disabled via control parameter “Fan operation” P52. When fan operation is
disabled, the fan symbol on the display disappears and actuating the fan button
has no influence. This function allows for using the controller in universal
applications such as floor heating with fan coil cooling etc.
In automatic mode, a dwelling time of 2 minutes (factory setting) is active. The fan
maintains each speed for at least 2 minutes before it changes to the next speed.
This minimum on-time can be adjusted from 1…5 minutes via parameter P59.
In automatic fan mode and with the room temperature in the dead zone, the control
valve normally is closed and the fan is disabled. With the fan kick function, the fan
can be released from time to time at low speed for minimum on-time (see above)
even if the valve is closed.
This function can be used to avoid damage from moisture due to a lack of air circu-
lation, or to allow a return air sensor to measure the correct room temperature.
Y
t [h:mm]
Q1
0
10385D22en
Periodic fan kick
Minimum
on-time
Periodic fan kick
Minimum
on-time
The periodic fan kick time can be selected individually for Comfort mode via
parameter P60 and for Economy mode via parameter P61.
Note: Fan kick value “0” means the fan runs continuously in the dead zone.
Fan kick value “OFF” means the fan is not running in the dead zone.
When the fan starts from standstill, it starts at speed 3 for 1 second to guarantee
safe fan motor start by overcoming inertia and friction (selected via parameter
P58).
Q
Q3
Q2
Q1
0
T
1 sec
When the electrical heater is switched off, the fan overruns for 60 seconds
(parameter P54) to avoid overtemperatures of the electrical heater or prevent
thermal cutout from responding.
In case of fan failure, the controller cannot protect the electrical heater against
overtemperatures. That is why the electrical heater must feature a separate safety
device (thermal cutout).
Fan operation as per
heating/cooling
mode, or disabled
Fan minimum on-
time
Fan operation in
dead zone
Fan start
Fan overrun for
electrical heater
Fan failure
