Esp Calculation For Duct May 2026

$$ESP = (P_supply + P_return) + P_accessories$$

1. Introduction External Static Pressure (ESP) is the cornerstone of HVAC airside design. It represents the total resistance that the fan must overcome to move air through the external components of the system—namely, the supply and return ductwork, grilles, diffusers, filters, coils, and sound attenuators. ESP does not include the internal pressure drop of the fan or air handling unit (AHU) cabinet itself. esp calculation for duct

$$\Delta P_f = f \cdot \fracLD_h \cdot \frac\rho v^22$$ $$ESP = (P_supply + P_return) + P_accessories$$ 1