Custom air-handler design and pricing, with the engineering written down

RWS 9 October 2026

Custom air-handler design and pricing, with the engineering written down

RWS takes an air-handler request, such as 10,000 CFM at 55 °F supply in Houston, and returns a complete design with a bill of materials, a price and the reasoning behind each step.

The selection method is written in plain language a senior engineer can review, and code does the arithmetic.
Air properties follow ASHRAE's 2017 psychrometric formulas, checked against PsychroLib.
Every design is checked before it is returned: airflow in range, every required component present and a complete bill of materials.

Release 1.1.0 is free under the MIT licence and includes a scripted demonstration for a hospital surgery suite.

76 seconds, captions only. The chart is drawn from the psychrometrics server's own output; each before figure is from the code as merged from the review, before release 1.1.0.