A system for controlling the flow of air through ductwork includes a foldably tensioned boot loadable air damper device and a method of installing same. The damper device includes an actuator having a retractable member and a pivoting member, wherein the pivoting member is operatively connected to the retractable member of the actuator. The damper device also includes at least one support base supporting the actuator and the pivoting member with respect to each other, a foldable damper blade attached to the pivoting member, and at least one tensioned hinge member operatively connected to the foldable damper blade for unfolding the damper blade. The damper device may be inserted through a register boot and into a ductwork when folded.