Controller that takes as an input the room air temperature TRoo and
the supply water temperature TSup,
and outputs the commanded mixing valve position yVal.
Based on the room air temperature TRoo, and the user adjustable parameters
for the minimum supply water temperature TSupMin,
the maximum supply water temperature TSupMax
and the room air temperature TRooMin
at which the supply water temperature is at TSupMax,
the controller computes a set point for the supply water temperature.
This set point is then used with the measured supply water temperature TSup
as an input to a PI-controller that computes the commanded valve position yVal.