# RE: [EnergyPlus_Support] Baseline Pressure Rise

Ivan,

The derivation below is in IP units, but it should give you some guidance.

As an example, pressure rise of 1.28 inches w.c. or 318 Pascals produces correct fan power for Sytems 1 or 2.

For System 3 or 4, it’s 3.32 inches w.c. or 826 Pa (No pressure credit)

For Systems 5 ? 8, 4.59 in. w.c. or 1142 Pa (No pressure credit)

 ASHRAE 90.1 Appendix G Fan Delta P Derivation (IP units) ΔP = BHP x η x 6356 CFM = (CFM x Fs + ΔPcf x CFM / 4131) x η x 6356 substituting BHP from CFM ASHRAE 90.1 Table 6.5.3.1.1A = (Fs + ΔPcf / 4131) x η x 6356 Note: Fs is the factor dependent on Baseline system type ΔPcf is the pressure drop adjustment (It is not applicable to Systems 1 or 2)

James V Dirkes II, PE, BEMP, LEED AP
www.buildingperformanceteam.com
Energy Analysis, Commissioning & Training Services
1631 Acacia Drive, Grand Rapids, MI 49504 USA
616 450 8653

From: EnergyPlus_Support@xxxxxxxxxxxxxxx [mailto:EnergyPlus_Support@xxxxxxxxxxxxxxx] On Behalf Of Ivan Mezzacapa
Sent: Tuesday, April 16, 2013 7:47 PM
To: energyplus_support@xxxxxxxxxxxxxxx
Subject: [EnergyPlus_Support] Baseline Pressure Rise

Hi!

how can i calculate pressure rise for baseline model?

Thanks!

Téc. Ivan Mezzacapa

Desenhista Projetista  de Ar Condicionado / Consultor de Eficiência Energética em Ar Condicionado

Celular: (11)9963-9326

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