The operation logic of the VRV is fully built-in inside the system and is proprietary for each VRF manufacturer. The system gets inputs from the user (e.g. desired comfort temperature) and from the surroundings (outside ambient temperature), and according to that data it implements its logic in order to get to the desired comfort conditions, utilizing optimal power consumptions.
The ability to adjust itself to the outdoor conditions is one of the main factors that makes these systems so efficient, compared to the traditional water cooled systems, based on chillers and fan coils.