Install — Refprop 91

"Seamless integration with Excel via the REFPROP Add-In"

In REFPROP 9.1, one of the most useful installation features is the automatic Excel Add-In setup. After a successful installation, the installer places REFPROP.xla (or .xlam) in the installation folder and can register it with Excel. This allows you to:

Introduction: The Gold Standard in Fluid Properties refprop 91 install

For decades, the National Institute of Standards and Technology (NIST) has maintained REFPROP (short for REfrigerant PROPerties) as the definitive program for calculating thermodynamic and transport properties of fluids. Version 9.1, while not the absolute latest release, remains widely used due to its stability and compatibility with older simulation platforms like EES, MATLAB, and LabVIEW.

However, installing REFPROP 9.1 on modern Windows operating systems (Windows 10/11) is not always plug-and-play. Legacy installer issues, 32-bit vs. 64-bit conflicts, and licensing hurdles are common. This article provides a step-by-step guide to a successful installation. "Seamless integration with Excel via the REFPROP Add-In"

Once your refprop 91 install is successful, integration with external tools is where the real power emerges.

Here is where many refprop 91 install attempts fail. You will see one of two screens: If you no longer have your serial or

If you no longer have your serial or license file, unfortunately, you cannot complete the installation. Contact NIST’s REFPROP support, but note they may not support version 9.1 in 2025.