Calculate preliminary booster pressure from supply pressure, required residual pressure, elevation, losses, and a visible user-entered margin.
Why it matters: Every pressure component must be visible before a booster duty point can be reviewed.
ΣCALCULATE · VERIFY · INTERPRET
Calculated result
Engineering evaluation
Calculation complete—verify project criteria
Required booster pressure (Pᵇ)12.32 psi
Unclipped pressure requirement (Pʳᵃʷ)
12.32 psi
Equivalent booster head (Hᵇ)
28.459 ft
Engineering interpretation
The entered pressure budget requires 12.32 psi booster pressure, equivalent to 28.4592 ft of fluid head.
Important limitations
Pressure-zone screen only. No hidden pressure or acceptance criterion is applied, and this result does not select a pump or establish compliance/acceptance. Confirm source minimum/maximum and seasonal variation, design flow, loss calculation, residual criterion, PRVs, surge, thermal expansion, redundancy, controls, curves, and uncertainty.
Motor-driven equipment
Estimate electrical demand and energy use
Use nameplate information and an operating schedule to screen motor input power, current, annual energy, and operating cost. Results update automatically.
Optional companion calculation
Choose the motor nameplate output-power convention.
Rated shaft output, not electrical input.
Used to estimate current; it does not change the hp-based energy result.
Use efficiency at the evaluated load point when available.
Use measured or defensible operating load rather than motor nameplate size alone.
Used only for the estimated current calculation.
Assumes all selected motors operate concurrently at the entered load.
Replace the profile with the actual occupied, process, or control schedule.
$/kWh
Use the applicable marginal utility energy charge; demand charges are not included.
Estimated result
Total motor input power (Pin,total)6.21 kW
Current per motor (I)
9.18 A
Total coincident current (Itotal)
9.18 A
Daily energy (Ed)
50 kWh/day
Annual operating hours (Hy)
2,080 h/year
Annual energy (Ey)
12,925 kWh/year
Annual energy cost (Cy)
$1,551/year
Equations and assumptions
Nameplate-based screening method
Horsepower is converted using 1 hp = 0.7457 kW. This estimate assumes steady average load and the entered operating-point efficiency. Voltage and power factor affect estimated current, but hp, load, efficiency, quantity, and schedule establish the energy estimate. VFD speed profiles, cycling, standby power, demand charges, and process variation require separate evaluation.
Subtract available supply pressure and clip negative required boost to zero.
Convert required booster pressure to fluid head.
Equation legend
Inputs and calculated quantities
Pˢ
Available supply pressure — psi or kPa
Pʳ
Required residual pressure — psi or kPa
Δz
Elevation rise — ft or m
SG
Fluid specific gravity — dimensionless
ΔPᴸ
Piping and device pressure loss — psi or kPa
Mᴾ
Project pressure margin — psi or kPa
Pᵇ
Required booster pressure — psi
Pʳᵃʷ
Unclipped pressure requirement — psi
Hᵇ
Equivalent booster head — ft
Applications
How this calculation is used
Building design
Assemble a transparent preliminary pressure budget.
Construction
Check elevation, pressure, and loss assumptions.
Commissioning
Compare measured supply conditions with a documented residual-pressure requirement.
Quality controls
Assumptions and limitations
Assumptions
Entered values describe one documented system and use a consistent unit, energy, pressure, elevation, and measurement basis.
Measurements are representative and synchronized where the calculation combines field readings.
Limitations
The result is a pressure-budget screen, not pump selection, pressure-zone design, code compliance, or acceptance.
Static/seasonal source variation, minimum and maximum pressure, PRVs, surge, thermal expansion, redundancy, controls, and equipment curves require project review.
Field use
Verification procedure
Confirm the calculation boundary, source documents, formula symbols, and units.
Record representative field values or approved project inputs and their sources.
Review the result against the applicable code, criteria, manufacturer data, and measurement uncertainty.
Common engineering mistakes
Combining values from different system boundaries, operating periods, temperature bases, or unit conventions.
Treating a calculated screening value as a hidden pass/fail threshold or final design decision.
Technical basis
References and source standards
International Plumbing Code, 2024The legally adopted edition and local amendments govern water, sanitary, storm, sump, and pumping requirements; protected code tables are not reproduced.
These engineering tools are provided for educational, preliminary evaluation, field verification, and commissioning support. Results depend on the accuracy of user-entered information and the assumptions stated for each calculation. Every colored status and comparison is a screening indicator only; project criteria, contract requirements, applicable codes, manufacturer instructions, measurement uncertainty, and authorized engineering judgment govern. The tools do not replace project-specific engineering analysis or the judgment of a licensed professional engineer.
