Corrigo ventilation 3.4 manu

Manual Corrigo Ventilation, revision R Chapter 5 Functional description 41
The recirculation setpoint can be configured as constant or offset. Constant means that the
recirculation setpoint will be used. Offset is based on an offset from the supply air setpoint.
To lower the temperature, it is possible to configure free cooling to be used during recirculation, if
the conditions for free cooling are fulfilled. Then, the recirculation damper closes, the supply and
extract air dampers open and the extract air fan starts (the supply air fan also starts, if it is not
already running). If the free cooling function is not configured for recirculation control and you
want to cool down the supply air via a low recirculation setpoint, the cooling battery will be used. A
max. room temperature can be configured for recirculation control. If the room temperature rises
above the set value (FS 25°C), recirculation will be stopped. When the room temperature has fallen
1 K below the set max limit, recirculation will start again if the start conditions are still fulfilled.
When running frequency controlled fans and using recirculation control you can, depending on the
type of fan control, configure a special pressure/flow offset for the setpoint or a manual output
signal for the supply air fan.
5.1.12 Change-over
Change-over is a function for installations with 2-pipe systems. It makes it possible to use the same
pipe for both heating and cooling, depending on whether heating or cooling is required.
A special analogue output signal, "Y1 Heating/Y3 Cooling", is used for Change-over control.
Switching between heating and cooling can be done in two ways. A digital Change-over input
signal is normally used. Open contact gives heating control and closed contact gives cooling
control. If the input has not been configured, change-over is handled by the internal controller
signal. The output signal will follow the two regular output signals "Y1 Heating" and "Y3 Cooling".
For heating control, the digital outputs ”Heating Activate” and ”Heat Step 1-4” are active. For
cooling control ”Cooling Activate” and ”Cool Step 1-3” are active.
If frost protection sensor has been configured, it will function in the usual way when heating is
active. However, when cooling is active, it will only be used for indicating temperature.
Three digital output signals, "Heat/Cool Step 1", "Heat/Cool Step 2" and "Heat/Cool Step 3", are
also connected with change-over. The signals can be used for reversing a step controlled heating
pump etc. See also section 5.1.4 Step controller Heating/ DX cooling.
The change-over function can be split if needed. If so, set the analogue output to “Split” and select
the function Y1 Heating/Y3 Cooling.
A digital function called “Split Sequence” is connected to the split signal. It is active when the
corresponding analogue signal exceeds 0.1 V.
5.1.13 Extra temperature sensor
The input signals ”Extra Sensor Temp 1”, ”Extra Sensor Temp 2”, ”...”, ”Extra Sensor Temp 5”, can
be used to add extra temperature sensors for supervision of temperatures that are not related to any
control functions. Each sensor has three alarms tied to it: High temperature, Low temperature and
Sensor error. “Extra temperature sensor 1” should be used for external setpoint input. “Extra Sensor
Temp 1” should be used for external setpoint input.
5.1.14 Extra flow sensors supply air and extract air
The input signals ”Extra SAF Pressure” and ”Extra EAF Pressure” can be used to display the flow
in the supply air and extract air ducts. The K- and X-constants for each fan are used to calculate the
flow.
5.2 Extra control circuit
An independent temperature control circuit for control of for example after-heaters. The circuit can
be configured to heating or cooling. It has an analogue input signal for temperature sensors and an
analogue output signal 0…10 V. There is also a digital output signal which is activated when the
analogue output signal is above 1 V and deactivated when the analogue signal is below 0.1 V. The
circuit can be configured to be active all the time or to be active only when the main unit is running
at normal speed.