High-altitude forced-air design check
Altitude Correction Calculator
Translate a sea-level forced-air cooling design to the project site. See actual pressure and density, the existing fan's same-speed derating, the airflow needed to restore mass flow, and the estimated change in heat-sink thermal resistance.
Project elevation2,500 m
1 · Site conditionAltitude + inlet temperature
2 · Reference designAirflow + pressure + Rθ
3 · Project decisionKeep, boost or resize
Site air condition
2,500 m · 40°C inlet · standard-atmosphere pressure
Absolute pressure—ISA estimate
Actual air density—At entered inlet temperature
Density ratio—Versus reference condition
ISA temperature—Reference atmosphere only
Available air mass per unit volume—
—
Option AKeep the original fan speed
Volumetric airflow—
Mass-flow capacity—
Fan/system pressure scale—
Corrected heat-sink RθSA—
Estimated base temperature—
Option BRestore reference mass flow
Required volumetric airflow—
Airflow increase—
Approx. fan speed factor—
System pressure target—
Fan-law power trend—
—
—
Sea-level reference vs. same-speed site estimate
Air density—
Mass-flow capacity—
Static pressure—
Cooling conductance—
How to use the result: standard-atmosphere pressure is a design estimate, not a weather forecast. The same-speed volume-flow assumption works when the same fan and system geometry are used because both fan pressure and system resistance scale with density. Always confirm the manufacturer's complete fan curve, speed limit, motor power and high-temperature rating.
For high-altitude forced-air design review, share the installation elevation, maximum inlet temperature, heat load, heat-sink drawing, enclosure flow path and full fan curve. Ecotherm can adjust the custom heat-sink geometry and airflow requirement without treating this estimate as a fan or system performance guarantee.