Building Energy Software Tools
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VariTrane Duct Designer

Reviews 1

Designing supply duct systems can be tedious... it involves time consuming calculations and requires assumptions about fitting size and performance. VariTrane Duct Designer streamlines this task and improves calculation precision, allowing you to optimize your designs from fan to diffuser and be more productive! The program consists of three applications:

  • Duct Configurator helps you model and size supply duct systems, as well as determine required fan static pressures. Re-size non-critical paths to reduce system first cost while optimizing the system design. Choose between the static regain and equal friction methods of design. Design constant volume or VAV systems with detailed control over diversity. Make VAV box selections directly in the program through a seamless interface with the Trane Official Product Selection System providing highly accurate system pressure and sound analysis. Three different fitting entry methods provide a wide array of choices for making fitting selections. Choose from all available fittings, customize the available fittings, or let the program select lowest loss fittings for the system.

  • Ductulator transforms Trane's popular manual duct sizing and layout calculator into a convenient PC-based tool. Use it to quickly size system components and determine the appropriate nominal duct size for equal friction applications.
  • Fitting Loss Calculator lets you quickly identify the optimal fittings and sizes for each duct section by comparing their efficiency and cost.

These applications, combined with an integral database of accurate performance data for hundreds of ASHRAE and United McGill fittings, let you model new or existing supply duct systems, whether round, rectangular, or flat oval. After you complete your design, print reports with detailed information about all aspects of the duct system, including bill of materials.

Expertise Required: 

Basic knowledge of duct systems, methodologies, and terms.


Mechanical engineers and system designers in need of accurate duct system modeling capabilities.


Enter data in easy to follow tab formatted interface. The tabs include Main, Fan, Sections, VAV boxes, Diffusers, and Spreadsheet.


VariTrane Duct Designer calculates airflows, velocities, detailed pressure drops, and diversity and produces thirteen different reports. Nine reports show calculation results including Project Summary, Sections, Diffusers, VAV Boxes, Trane Acoustical and Selection Data, Run-out Analysis, and Fitting and Section Bill of Materials. Four reports are dedicated to entered values. The critical path is clearly marked for quick analysis.


Ability to optimize design by re-sizing non-critical paths and adjusting for thermal and leakage changes. Make detailed VAV selections with acoustical analysis directly in the program. Ability to make detailed fitting analyses. Model new or existing systems making large-scale changes quickly and easily through the spreadsheet editor.

United States
Major Capabilities: 
HVAC System Selection and Sizing
Building Type: 
Subsystem Level
Free To Try
Last Software Update: 
21 September 2012
Last Entry Update: 
19 September 2018
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