AIAS RC Techsheet IMO
12 / 26 | AIAS Room controller - installation and operation instruction
CO2 sensor and VAV control
RC can be set to all of the above control modes. When RC are set to VAV control, the control mode is combined with a CO2 control
function.
In control mode Heating/Cooling with VAV-control, the CO2 concentration in the room will make the VAV damper, cooling output UO2,
open. The function is linear and the damper works between the congured min. ow (FS=20 %) and 100 %, depending on the CO2
concentration in the room. If the CO2 concentration drops below the congured min. limit, the damper will stay on the minimum allo-
wed air ow. When the CO2 concentration rises, the damper will open linearly until reaching the congured CO2 max. value, at which
point it will be 100 % open.
Full range change-over determined heating/cooling control by VAV combined with CO2 control.
This mode allows to control the room temperature by VAV either in heating or in cooling mode, depending on the change-over status.
Control value Y1 is active for this function. As described above, the CO2 control over Control value Y2 operates in paralel. The Higher of
the control values is forwarded to the alalog output for air ow control by VAV.
This mode is activated by setting parameter 11 (Control mode) to value 10 (see page 29)
Minimum limit on analogue 0...10 V actuators
The minimum limitation on the analogue output is only active in Bypass, Occupied and Standby. If the operating mode is Unoccupied
or Off, the damper will be closed (0 V on the analogue output). See table below:
Operating mode Min. limit VAV output (Y2)
Bypass 20 % 2 V
Occupied 20 % 2 V
Standby 20 % 2 V
Unoccupied 20 % 0 V
Off 20 % 0 V