Go to File > Options > Trust Center > Trust Center Settings > Trusted Locations . Add your REFPROP folder (e.g., C:\Program Files\REFPROP ) and check "Subfolders of this location are also trusted".
: For educational or student use, a free "Mini" version is available that follows a similar installation wizard process. 2. Linking with Microsoft Excel
: Ensure the box for Refprp91 is checked in the list and click OK . refprop 91 install
While REFPROP 9.1 predates widespread Python support, you can still call its DLL using ctypes :
By following this guide—preparing your system, running the installer with administrative privileges, correctly applying your license, and verifying the installation—you can avoid the common pitfalls that frustrate many users. Remember that the most frequent issues stem from missing VB6 runtimes, antivirus interference, or lost license files. Go to File > Options > Trust Center
: Go to the Developer tab and click on Excel Add-ins .
Ensure all fluid files ( .fld ) and mixture files ( .mix ) are checked. This guarantees you have access to the full database of pure fluids and standard mixtures (like R410A or Air). Remember that the most frequent issues stem from
REFPROP 9.1 Install Guide: Comprehensive Setup and Configuration
NIST REFPROP (Reference Fluid Thermodynamic and Transport Properties) is the industry standard for calculating the thermophysical properties of fluids. While REFPROP 10 is the latest edition, version 9.1 remains widely used in engineering labs, academic research, and legacy industrial pipelines.
: Install the official wrapper using pip install ctREFPROP .
If you encounter issues during installation or while using REFPROP 9.1, refer to the: