Regio Midi manual
Chapter 7
Control modes
33
Output signal
Heating 2
Heating 1
0 %
100 %
100 %
48 %
52 %
Heating demand
Control mode 2: Heating or cooling via change-over
This control mode is used 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.
Switching between heating and cooling mode can be performed either by using a digital or an
analogue input. Only one output is used to control the actuator (UO1). See more in the chapter
Change-over function.
Control mode 3: Heating/Cooling
In control mode Heating/Cooling, the controller functions as a heating controller when the
room temperature is lower than the basic heating setpoint plus half the neutral zone. The
neutral zone is the difference in temperature between the heating setpoint and the cooling
setpoint. When the room temperature exceeds this limit, the controller becomes a cooling
controller. There is a hysteresis of 0.1°C when the controller changes from heating to cooling
controller and vice versa. When the controller is heating, it regulates according to the basic
heating setpoint plus the setpoint adjustment, and when it is cooling according to the basic
cooling setpoint plus the setpoint adjustment.
Output signal
Cooling
Heating
0 %
Temp (°C)
100 %
SP
heating
SP
cooling
Neutral zone
Control mode 4: Heating/Cooling with VAV-control and
forced supply air function
Like control mode Heating/Cooling but the cooling output is controlling a supply air damper
(sub-tempered supply air). When the ventilation is forced (See
Chapter 12, Special functions
),
the cooling output is set to full cooling (full supply air volume), regardless of what the
controller output signal is.
For VAV control, several basic flows exist for supply air depending on the current running
mode.
