Table 2-20 Fan kick-start configuration settings.
Configuration setting
Description
Fan kick-start time (sec)
The period of time (in seconds) that the fan kick-start function is active.
2.5.5
Fan afterblow
Fan afterblow is a control function that can be used as a safety precaution when an electrical heating battery
that is placed in the ductwork is used to provide heating. For example, when auto fan mode is in use and the
heating demand decreases to zero, the fan stops while the electrical heating battery typically remains hot for
a while longer. The fan afterblow function can then be used to make the fan run for and extended period of
time to allow for the electrical heating battery to cool off.
The fan afterblow function is enabled via the
Fan afterblow mode
configuration setting.
The fan afterblow function is activated when the applicable heating output signal, as specified via the
Fan
afterblow mode
configuration setting, decreases to zero.
When the fan afterblow function is active, the fan runs in afterblow mode for the period of time specified by
the
Fan afterblow time
configuration setting. A minimum fan speed during fan afterblow can be set via the
Fan afterblow minimum speed
configuration setting.
After the fan afterblow time has expired, the controller reverts to normal fan control, that is, auto or manual
mode.
The fan afterblow configuration settings are described in
Table 2-21 Fan afterblow configuration settings.
Configuration setting
Description
Fan afterblow mode
Off:
Fan afterblow is disabled (default setting).
After heating 1:
Fan afterblow is activated when the heating output signal that is associated with
heating sequence Y1 decreases to zero.
After heating 2:
Fan afterblow is activated when the heating output signal that is associated with
heating sequence Y2 decreases to zero.
After heating 1/2:
Fan afterblow is activated both when the heating output signal that is associated
with heating sequence Y1 or heating sequence Y2 decrease to zero.
Fan afterblow minimum speed This setting is used to set a minimum fan speed during fan afterblow.
Off:
The minimum allowed fan speed is zero (default setting).
Speed 1:
The controller ensures that the minimum fan speed is the configured fan speed 1.
Speed 2:
The controller ensures that the minimum fan speed is the configured fan speed 2.
Speed 3:
The controller ensures that the minimum fan speed is the configured fan speed 3.
Fan afterblow time (sec)
The period of time (in seconds) that the fan afterblow function is active.
2.6 VAV control
The variable air volume (VAV) control function is used to manage the behaviour for a damper that is
controlled by the analog VAV output signal.
The VAV control function enables the controller to regulate based on:
✓
Cooling demand
The VAV output signal is controlled based on the cooling setpoint and the current room temperature.
✓
Fresh air demand
The VAV output signal is controlled based on the CO
2
setpoint and the current CO
2
level in the
room.
Regio
Eedo
manual, Rev. D
37