AlliedSignal 131-9b APU Operating Bleed Load Limit
AlliedSignal 131-9b APU as fitted to the B737NG has a bleed load operating limit at sea level,60F day of 160pounds per minute at 60psi.The ECU will modify this output pressure and flow during MES mode depending on actual atmospheric conditions to allow for changes in surge margins.
Best info i could find at hand,referance was AMM part 1 Chapter 49-00-00 page 5.
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