OFF         - Pack signalled OFF.

AUTO      - With both packs operating, each pack regulates to low flow

                 - With one pack operating, operating pack regulates to high flow in flight                       with flaps up

                 - When operating one pack from APU (Both engine BLEED Air Switches                      OFF), regulates to high flow

HIGH       - Pack regulates to high flow

                - Provides maximum flow rate on ground with APU BLEED Air Switch ON.

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