Based on the provided video transcript snippet, an air injection iron filter begins its process by the system building an air (presumably referring to creating an air pocket or bubble within the filter).
This initial step is presented as the core mechanism by which the filter operates using just air. The reference also notes that this type of system can remove manganese from your water, although this capability operates "within certain parameters."
The snippet specifically asks how it's possible for the system to work using only air, and the explanation provided starts with the action of the system building an air.
Therefore, according to this reference, the fundamental working principle starts with the system creating an air component internally.
