Assortment / System Description

Fan coil application
Control of staged fan
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The fan must be switched on if room temperature measurement is made using
a return air sensor in the fan coil 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 fan activities 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.
Locking is a binary signal to protect fan coil 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.
The fan 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/AirFlCReq
Return air sensor
Locked by electric
heating coils
Start of fan by heating
demand