Assortment / System Description

VAV application
Return air sensor
18
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18.8 Return air sensor
The volume air flow must be available if room temperature measurement is
made using a return air sensor in the VAV system, to correctly acquire the
actual room temperature. A minimum air volume is enabled in the dead zone by
default for the operating mode Comfort on the DXR2. The parameter cannot be
changed when using a return air sensor to measure room temperature.
In this case, note that a conventional room temperature sensor must be
configured at the DXR2 input. The return are temperature sensor is then
connected instead of the room temperature sensor. The room is now
temperature controlled per the measured value from the return air sensor.
DXR2 does not support interval-type air volume to periodically measure room
temperature with the return air sensor.
Also note that DXR2 temperature control in the room can only have one
measured return (temperature sensor) which is always configured and
connected at the input of the room temperature sensor. The available
configuration for a return air sensor is used for visualization on DXR2.
18.9 Locked by electric heating coils
Locking is a binary signal to protect VAV equipment. The application locks
electric heating coils even if no air flow is available through the fan. Or enabled
if air flow is available through the fan.
18.10 Start of air volume flow by heating demand
Volume flow is started for active heat or refrigeration demand in the room. The
signal is sent to the fan from the heat or refrigeration register.
Description Name
Display of heat/cooling request in the room. It
starts the fan to meet the heat request.
AirFlHReq