# Pressure Drop Calculation

The Pressure Drops application allows users to fill in the loss coefficients of the individual ductwork components for the selected route. Based on these coefficients and the air flow data through the pipe, which are taken from the HVAC system values, the application calculates the total pressure drop of the selected route. Based on this calculation, the designer can determine the critical route to properly dimension the system.

The calculation of the route pressure drop is very intuitive. The user selects the route on which the pressure drop needs to be calculated. In the main Pressure Drops dialog, the route elements with their properties are displayed. The user assigns the specific loss coefficient for each element along the selected duct route. The pressure drop values for straight and flex ducts are calculated automatically by the application. The application then calculates the total pressure drop value of the selected route, according to which the designer can evaluate the HVAC system. In case of repeated calculation, it is not necessary to enter the values of the specific loss coefficients again, the application saves the entered values for each instance.

<figure><img src="/files/usUvh3QS4baSOp8rkSlG" alt=""><figcaption><p>Pressure Drops main dialog with dcut route pressure drop calculation</p></figcaption></figure>


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