Heat Exchanger, Coil & Radiator Manufacturing worked example

Coil Pressure Drop with baseline pressure drop of 50 psi: a worked example

Here is what the math looks like when conditions slip. We hold every other input steady and drop baseline pressure drop to 50 psi, then walk the calculation through step by step. Estimate adjusted coil pressure drop from a measured or specified baseline pressure drop, a flow or fouling correction factor, and test duration.

The inputs for this scenario

  • Baseline pressure drop: 50 psi (the input this scenario stresses; the baseline uses 100)
  • Flow or fouling correction factor: 1.2 x (held at the documented default)
  • Test or operating duration: 8 hr (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Adjusted pressure drop = baseline pressure drop × flow or fouling correction factor.
  • Total load works out to 60 psi at these inputs, and this is the headline figure for the scenario.
  • Pressure drop per test hour works out to 7.5 psi / hr at these inputs.
  • Baseline pressure drop works out to 50 psi at these inputs.
  • Correction factor works out to 1.2 x at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where baseline pressure drop sits at 100 psi and the headline result is 120 psi, this scenario comes in 50% below the baseline at 60 psi.
  • The practical read: the gap between this scenario and the baseline is entirely attributable to baseline pressure drop, so recovering it is worth quantifying in dollars before considering equipment or staffing changes. It scales drop with a single linear correction factor; real pressure drop varies with the square of flow, so the factor only holds near the reference flow rate it was derived at.

Results at a glance

  • Total load: 60 psi (headline result)
  • Pressure drop per test hour: 7.5 psi / hr
  • Baseline pressure drop: 50 psi
  • Correction factor: 1.2 x

Run it with your numbers

  • To rerun this with your own numbers, open the live Coil Pressure Drop calculator, set baseline pressure drop to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.