CoolSim 5.4 changelog

CoolSim 5.4.180 preview 2

The desktop build of October 2, 2026, with 7 changes. It is built on CoolSim 5.4.180. A newer preview has replaced it on the preview download page.
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Changed

Can make a model solve to a different answer than before.

Sloped polygon blocks keep their slope

Polygon blocks extruded along X or Z, such as a sloped soffit, were sent to the solver flat. They now reach it with their slope, so a model with one can solve to a different answer than it did from earlier versions.

New

Installs beside your current CoolSim

The preview installs as CoolSim 5.4 Preview, next to the CoolSim you already have, so you can try it on real models and go back at any time. Both use the same models, libraries, work area and sign-in. The preview doesn’t take over .csp files, so double-clicking a model still opens your current CoolSim. Run one at a time: the two share one object library database.

Silent install for IT

CoolSimSetup_5.4.180_preview2.exe /S installs unattended, with the libraries and work area in place.

Improved

Moving a group no longer lifts ceiling grilles or floor cutouts

Each move of a group used to raise every ceiling grille in it by 0.5 mm and every floor cutout by 1 mm. A grille left even 0.5 mm off the ceiling showed almost no air through it in the solved job. Group members now keep their height, the same as when you move a single object. Models you have already saved are not changed.

Undo and redo are dependable

  • Undoing a group move puts every member of the group back.
  • Undo works after Redo.
  • A new edit clears the Redo history, so Redo can no longer replay an old change on top of new work.
  • Undo keeps recording after you cancel a Save or Open.
  • Undo with nothing left to undo no longer shows an error.
  • Changes made in an object’s properties dialog can be undone.
  • Undo and Redo from the menu now update the 3D view.

A failed export sends nothing

If exporting a model fails partway, CoolSim now stops, names the file that failed and sends nothing. Before, it could submit the incomplete model as a job.
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Something working differently?

Tell us your CoolSim version and what you did. We’ll tell you which change it is, and what it means for your model.

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