Lawrence Berkeley National Laboratory (LBNL) has developed a new software tool called Ctrl-flow with funding from the U.S. Department of Energy (DOE), which is available for free.

The initial release of Ctrl-flow allows designers to input project information, the desired systems, and their configurations. The tool will then provide an edited sequence based on ASHRAE Guideline 36-2021 that is specific to the selected options.

Currently the tool supports the following:

  • Options for SI or IP units
  • Code compliance for ASHRAE 90.1 / 62.1 or California Title 24
  • Selection of climate zones
  • Airside systems including multiple-zone VAV air handlers and cooling-only and reheat VAV terminals

Future releases of the tool will include:

  • Support for a broad range of systems including all systems in Guideline 36
  • The ability to provide additional project information and then download more detailed documentation including:
  1. Points lists
  2. Systems diagrams
  3. The control logic for the specified sequence in the control description language (CDL) as well as in the control exchange format (CXF)
  4. A Modelica model of the HVAC system selected that can be used with tools such as the Spawn of Energy Plus.

The tool is designed to help support the needs of HVAC system designers, control contractors, commissioning agents, and energy modelers in evaluating and deploying advanced control sequences.