The S&P Duct Calculator by SolerPalau is a free, easy-to-use app available on Android devices. It is a comprehensive tool that can be used for a variety of calculations related to HVAC installations. The app is divided into four areas, which allow for three different calculations to be carried out quickly and with ease.

The first area is the Diameter Converter, which allows users to convert circular ducts to equivalent rectangular ducts. The second area is the Calculator of different ventilation parameters, which enables users to obtain the diameter, air speed, airflow, and dynamic pressure of their installation. The third area is the Pressure Drop Calculation Tool, which can be used for straight sections and duct system elements. Lastly, the Units Converter area can transform speed, airflow, power, and pressure units for other equivalents in different scales.

Overall, the S&P Duct Calculator is a useful tool for HVAC professionals and DIY enthusiasts alike. It is easy to navigate and provides accurate results, making it a convenient addition to any toolbox.