An automatic airflow balancing valve, including: a housing having an inlet and an outlet and defining a flow path therethrough; a valve disc operatively connected to the housing and disposed within the flow path; and an airflow volume calibrating assembly disposed in the flow path and operatively connected to the valve disc and the housing to pivot the valve disc to a home position associated with a desired constant airflow volume. The airflow volume calibrating assembly may include an adjustment element that extends toward at least one of the inlet or the outlet.