Skip to main content
You are here: 🖋️ System Design

Ducts

In the design process, horizontal Ducts can be drawn from different types such as Mains, Branches, and Connections, each with distinct Settings and sizing parameters.

Drawing Ducts (and using h2x in general) is easier with a mouse

How It Works

You can see the Duct Height in the bottom left corner of the screen, and can control it with your keyboard as you draw

Step-by-step

  1. Select the Correct Type of Duct:

    Mains: Used for larger, primary ducts in the system.

    Branches: Small linking sections to attach Grilles.

    Multi-Duct: Multi-duct mode allows you to draw multiple ducts simultaneously. The number of ducts that will be drawn are highlighted in the circle around the cursor. For example, two ducts in the circle = two ducts will draw.

  2. Drawing Ducts:

    Left-Click to place the starting point, (commonly on a Grill, Equipment connection, or blank space).

    Move the mouse to the next desired point and Left-Click to add that point as a new fitting/bend in the layout.

    Adjust the Height of the duct using the Arrow Keys on your keyboard whilst you are drawing.

    The height is displayed in the bottom left of the screen.

    Escape the drawing tool by pressing Escape on your keyboard or clicking the top-left exit icon.

  3. Connection Indicators:

    Solid Color Ducts: Properly connected to Equipment and/or Grilles.

    Semi-Transparent Ducts: Not properly connected to Equipment and/or Grilles.

    Red Circles: Indicate the Duct end is not connected.

  4. Editing Ducts:

    Click and drag ducts to move them to a new position.

    Click a duct to view and edit its Properties in the properties panel.

    Right-click and Select Similar to apply edits to multiple similar ducts at once.

Duct Properties

General Tab

  • Name: Specify a unique identifier for the Duct.

  • Flow System: Select the type of fluid system (e.g., Hot Supply).

  • Color: Assign a Color to the duct for easier visual differentiation.

  • Length: Automatically computed based on the drawn duct, but can be overridden.

  • Height Above Floor: The height of the duct relative to the floor. Ensure this aligns with the rest of your system to avoid errors.

Note the Height field is the Level Height plus the Height Above Floor

Technical Tab

  • Network Type: Review and edit the type of duct network (e.g., Mains).

  • Max. Velocity: The maximum allowable velocity for fluid flow. Can be overridden from the default.

  • Max. Pressure Drop: The maximum allowable pressure drop per unit length of the duct. Can be overridden from the default.

  • Material: Review and edit the default Material (e.g., steel, PVC).

  • Sizing Mode: Choose how duct sizes are calculated:

    • Recommended Sizes Only: Uses standard sizes from the catalog

    • Step Increment: Allows sizing in set increments (e.g., 50 mm/2 inches).#

    • Unrestricted: Provides the exact calculated size, which may not correspond to real-world duct sizes

  • Shape: Select between Circular or Rectangular duct shapes. 

  • Diameter: Computed based on the flow rate and system Settings, but can be overridden.

Troubleshooting Ducts

  1. Check Connections: Ensure Ducts are properly connected (solid color) and not semi-transparent.

    Verify no red circles are present at duct ends.

  2. Connection to Equipment: Confirm that cap connections disappear when ducts connect to Equipment or Grilles properly.

  3. Adjusting Height: Check the duct Height and ensure to use the arrows on the keyboard to define the duct height when drawing.

  4. Editing Properties: Access the duct Properties to review/edit System, Material, Diameter, and other attributes. This will highlight the duct yellow so you can easily identify its had its default parameters overridden.