The pipe between pump and chamber restricts flow. Conductance ( C ) (L/s) reduces effective pump speed:
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FINAL PUMP SIZING: Corrected Speed w/o Conductance (m³/h) =B13 B8 -> 732.8 Effective Speed with Conductance (m³/h) =1/( (1/B14) + (1/(B7/3.6)) )? (unit careful) Simpler: Required Pump Nominal Speed (m³/h) =B14 1.2 (20% conductance reserve) -> 879.4 The pipe between pump and chamber restricts flow