Flash fraction from pressure let-down, flash steam and residual condensate, flash vessel and vent condenser sizing basis, and the yearly value and payback of a condensate return project.
USD 39 one-time purchase
Download the sample report (PDF)
Need it once? Use it online: check your data free, unlock results from USD 9 for 3 runs.

What it does
Flash fraction
From the pressure let-down for saturated or subcooled condensate, with IAPWS-IF97 steam properties built in as formulas.
Flash steam use
Flash steam to a low-pressure header, vented, or condensed in a vent condenser on the makeup water, with the heat lost when vented.
Flash vessel sizing basis
Steam volume flow, allowable velocity, diameter for steam and hold-up, height or length and the flash steam line size.
Vent condenser basis
Duty, the heat the makeup water can take, makeup flow needed and the temperature approach.
Value and payback
Fuel, water and chemicals saved by returning condensate, with gross and net annual saving, simple payback and return.
Current and proposed
Both cases side by side, what-if tables for the return and the vessel pressure, ranked findings and three charts.
Built for engineers
- Visible formulas — nothing hidden, so you can check every step.
- Fully referenced — methods from the standard references, checked against their published worked examples.
- Safe to share — sheets are protected against accidental edits, with an open password so you can still customise.
- Built-in input checks — clear warnings for impossible inputs and values outside typical ranges.
For engineering estimates; verify against site data. Code-based methods are aligned with the publicly documented procedure; they are not a licensed reproduction or a certification.
Preview the workbook
Real pages from the workbook with its built-in example loaded (example data, not a measured plant). Choose a page below, or select the large image to enlarge it.
Specification and checks
| Format | Excel workbook (.xlsx), no macros |
| Version | v1.0 |
| Works in | Excel 2010 or later, Windows and Mac |
| Units | SI, US and British, mixed freely |
| Includes | Guide tab with method and references, calculator, print-ready report |
| Checked against | 178 recalculated runs against an independent IAPWS-IF97 Python model: every combination of the four method selectors, random and hand-picked inputs, US and British units and 66 edge cases; largest deviation 4e-12 in the same units. |
| Free version | Try the free flash steam calculator |
Online tool or Excel workbook?
A free web calculator for the key figures of this topic is on the free calculator page.
| Online tool | Excel workbook (this page) | |
|---|---|---|
| What it does | The same sheet as the Excel workbook, run in your browser | Flash fraction from pressure let-down, flash steam and residual condensate, flash vessel and vent condenser sizing basis, and the yearly value and payback of a condensate return project. |
| Cost | Check your inputs free. Results: 3 runs for USD 9, or every online tool for USD 15 a month (USD 99 a year) | USD 39 once, yours to keep |
| Input checks and findings | Every input checked; findings with the unlocked results | Every input checked, with findings and recommendations |
| Report for your calculation file | Printable results sheet | Print-ready report with your plant, tag, document number, revision and sign-off |
| Formulas | Method described in the guide | Every formula visible in its cell |
| Save, edit and rerun your cases | Each run separately | Yes: keep and edit your own file |
| Works offline, on a plant PC | No, needs the internet | Yes: Excel 2010 or later, Windows and Mac |
Online access and the Excel workbook are separate licences: one does not include the other.
Compatibility, licence and support
| File | Excel workbook (.xlsx), no macros, version v1.0; works in Excel 2010 or later on Windows and Mac. Sheets are protected against accidental edits, with an open password so you can customise. |
| Licence | Single user. A team licence (up to 5 named users) is 3 × the shop price; site licences on request — licence terms. |
| Updates | Updates to this major version are included; download them again from the link in your receipt. |
| Support | Email [email protected] with your order number — questions on the method, your inputs or your results are welcome. |
| Refunds | If the tool does not work as described, or has an error we cannot fix, email [email protected] with your order number within 14 days of purchase and we will refund you in full. Refunds are not offered for a change of mind once a file has been downloaded. Read the full refund policy. |