The General HVAC Concept

The amount of analog inputs that need to be sensed by a
modern HVAC feedback control system usually will include
Heater, AC, Inside Air, Outside Air and multiple Seat
Temperature Inputs. However, other criteria such as
Sunlight-Intensity as well as the Inside Humidity will be
additional parameters based on which the HVAC will be
controlling the compartment’s climate as well. This sensor
matrix leads to the following generic block diagram:

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