Version
Document
Preliminary 003
Access V4.X Configuration manual
20 (33)
2019-05-13
Enable support control when ventilation unit is shut down
•
No
•
Yes
Extract air fan running during support control
•
No
•
Yes
Settings:
Data & Setings > Demand control > Support Control >
Support control is normally used when room temperature control or extract air control has been
configured. When extract air control is configured a room sensor must be installed. “Support control
Heating” or “Support control Cooling” will run if Support control is configured, the running mode is in
Off-state (timer control OFF and not in extended running) and if conditions call for support control (see
below). Minimum run time is settable 0 to 720 minutes (FS= 20 minutes).
Support control can also be configured when supply air temperature control is used, if a room sensor is
installed. The controller uses the configured min. (FS=15°C) and max. (FS=30°C) limitation values as
support control setpoints. However, in this case the min. and max. limitation values cannot be changed.
To change the values, temporarily configure room control, change the min. and max. values and then
change back to supply air control.
Support control can also be configured to start only with the supply air fan. In this mode, the extract air
fan is not active. This requires a digital output to be configured, which controls the recirculation damper
to open completely so the supply air fan can circulate the air to and from the room. The digital output is
called “recirculation damper”.
Support control heating
Demand for support control heating is when the room temperature is lower than the start value which is
settable 0 to 30°C. The fans will run at the preset speed, the heater and the heat exchanger are
controlled by the supply air temperature controller with the configured max limitation for the supply air
(FS=30°C) as setpoint and the cooling is shut off (0%). Support control heating stops when the room
temperature rises to the stop value and the minimum run time has been exceeded or the running mode
changes to ”On”.
Support control cooling
Demand for support control cooling is when the room temperature is higher than the start value which
is settable 20 to 50°C. The fans will run at the preset speed, the heater and the heat exchanger are shut
down (0 %) and the cooling is controlled by the supply air temperature controller with the configured
minimum limitation (FS=15°C) as setpoint. Support control cooling stops when the temperature falls
below the stop value and the minimum run time has been exceeded or the running mode changes to
”On”.