Formula and Inputs
Total pressure loss combines straight-duct friction, fittings, filters, coils, dampers, and terminal-device losses.
VoltCheck24 Engineering Calculator
HVAC Duct Pressure Loss and Fan Motor Calculator
Estimate duct friction loss, total static pressure, airflow velocity, and fan motor power for HVAC and cleanroom ventilation systems.
How to use this calculator
- Collect the values below from the equipment nameplate, data sheet, or field measurement.
- Enter values using one consistent unit system and use worst-case operating conditions.
- Review the result, margin, and engineering note before selecting hardware.
- Cross-check the result with the related calculator and save the review for your project record.
Input checklist
- Design airflow
- Duct dimensions and length
- Fittings, filters, and coils
- Fan efficiency and operating temperature
Industrial Use Cases
Use this page for factory ventilation, cleanrooms, exhaust systems, process air, and industrial supply-air design.
Engineering Note
Use certified fan curves at the actual airflow and static pressure. Check filter loading, leakage class, noise, temperature, and fire-damper requirements.
FAQ
Why does a dirty filter change fan selection?
Filter pressure drop rises as the filter loads, so the design point must include a clean-to-dirty operating range.
Should I use nominal or actual airflow?
Use the required operating airflow at the design temperature and pressure condition.
Preliminary engineering reference only. Confirm final selections against current standards, project specifications, and manufacturer data.