Checking Duct Sizing Data

A valid HVAC Route is loaded in the Duct System Sizing. The route is mained to have optimum duct sizing for a given characteristics of flow. The Load or Calculate command will check for any missing data in the Duct Sizing table necessary for all calculations to complete and will highlight the missing data in the summary table. When all data is complete the recalculate will take revised values in computing.

Set the Limit Duct Velocity in the Settings, Duct Sizing Data.
This value limits the flow in the system start. For duct elements, the velocity above this value indicates out of range and needs to be set within the limit duct velocity.
For each openings, set/check the desired values for terminal Airflow.
The terminal units —Grilles, Diffusers, or Plenum Boxes used in the route take Air Flow Rate (CFM) values set in DataGroup Instance Data. The route terminals are connected using the terminal fittings that are expected to deliver required airflow at the openings.
Set the Outlet Pressure (in. mg) DataGroup Property of the terminal unit as per what diffuser/grille specifies.
When a non-zero the discharge pressure is taken for computing it affects fans static pressure.
Click Calculate. The Critical Route Path dialog pops up indicating the critical paths and the value of pressure loss. The corresponding duct sections to these paths in the summary tables are highlighted in different color. The calculate command begun check on Openings for valid flow rates, followed by Main Duct velocity and then highlights missing or out of range values in different color cells.
Group By: Duct Element to examine the section rows category wise for velocity and pressure values .
The sizing system computes the velocity and pressure parameters and assign to each duct component.
Revise the velocity or duct pressure to arrive at acceptable pressure loss.
You can lock one of the parameters using the right-click > lock panel and keep it unaltered in the calculation.
For a Duct, click Duct Size to pick an alternate size from the pull down list provided.
This will not affect the calculated result, though helps in choosing a duct of suitable dimension matching with intended design and space requirement.