See the calculator’s supported inputs, how it breaks down power, and what its preliminary sensible-capacity result can—and cannot—tell you.
Choose pump, fan, or sensible thermal load in SI or US customary units.
01 / UNIT SYSTEMS
The calculator handles three separate checks. Each one has its own inputs and a result breakdown for an early estimate.
Estimate power at a requested steady-state flow and total dynamic head.
Estimate power for a single preliminary airflow and static-pressure duty point.
Estimate a preliminary sensible capacity from room, envelope, ventilation, and internal-gain inputs.
02 / METHOD
The tool supports both SI and US customary units. Keep each calculation in one consistent unit system, then inspect the returned breakdown, assumptions, and limitations alongside the result.
Choose pump power, fan power, or thermal load to match the duty point you want to check.
Enter the inputs for that mode and use either SI or US customary units.
Review the component breakdown and the assumptions and limitations shown with the result.
03 / SCOPE
The calculator is a screening aid for early decisions. It does not replace detailed system analysis or qualified equipment selection.
They do not select a manufacturer or model or check equipment curves. Pump checks also omit NPSH, viscosity, controls, and the system curve. Fan checks omit sound, surge or stall, system effect, filtration, and controls.
It estimates sensible load only. It excludes latent load, solar orientation and shading, detailed assemblies, duct losses, psychrometrics, code compliance, and Manual J or engineer sign-off.
Values are early estimates, not certified equipment selection, a final design, or a cooling or heating recommendation. Fan air properties are not corrected for altitude or temperature.
Kernspan / HVAC
Open the interactive calculator to enter the inputs for your pump, fan, or sensible thermal-load estimate.