a plurality of tunnels defining a plurality of separate air flow pathways, wherein at least one tunnel of the plurality of tunnels is an active tunnel and at least one tunnel of the plurality of tunnels is a redundant tunnel;

a first air select at a first end of the plurality of tunnels;

a second air select on a second end of the plurality of tunnels, the first end being opposite to the second end; and

a plurality of dampers within each of the first and second air selects, the plurality of dampers configured to change an air flow therein to block air flow through the active tunnel and allow air flow through the redundant tunnel, wherein at least one damper of the plurality of dampers in each of the first and second air selects is in air flow communication with a corresponding one of the tunnels of the plurality of tunnels and another damper of the plurality of dampers in each of the first and second air selects is in air flow communication with a damper of the plurality of dampers in an adjacent one of the first and second air selects.