CoolSim 5.4.180 preview 5

The desktop build of October 11, 2026, with 25 changes. It is built on CoolSim 5.4.180. A newer preview has replaced it on the preview download page.

Changed

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

The Rack Heat Loads import reaches the solver

In CoolSim 5.4.180, File → Import → Rack Heat Loads (CSV) never changed the job: a rack row’s load went to a field the solver does not read. On a row set rack by rack, 0 kW became 1,000 W and a blank became −1,000 W, which the solver treats as a heat sink, and each rack’s airflow stayed sized for its old load.

The preview sets every rack in a row you name, recomputes each rack’s airflow from its expected temperature rise as the rack editor does, and ends with a list of every line it left alone and why. Results change for any model whose heat loads came from this import.

Apply in Details saves every row you changed

Details is the table of every object of one kind, opened from the Pre-Simulation Report or a group. In 5.4.180, Apply skipped the row the cursor was still in, so editing one rack row and pressing Apply changed nothing in the job. A tile row’s changes never reached the row, and a rack row set by temperature rise had its airflow recalculated from its heat.

The Rack Builder keeps what you built

A rack holding only blanking panels dropped out of the job. A server added from the rack row editor in a slot a blanking panel had held stayed a blanking panel, lost its heat, and the job could not be sent.

The share to liquid is a percentage

The rack’s field is a percentage of its heat, but the 5.4.180 Rack Builder wrote the servers’ liquid watts into it and left them there when the last server was removed. On our test machine, removing a 5,000 W server at 20% left 1,000 in the field, and the emptied 4,000 W rack went to the solver with 40,000 W to liquid.

Sensor connections reach the solver without opening Sensor Connections

In CoolSim 5.4.180, the solver learned which sensors are the room’s reference sensors, and which ones each VFD cooling unit follows, only if Sensor Connections had been opened since the model was. A model opened and sent straight away went with no reference sensors and with every sensor marked as a plain sensor. The preview takes both from what the model saves.

Reference sensors combined by RMS use every reference sensor

In 5.4.180, a room whose reference sensors were set to combine by root mean square sent the solver a setting it does not recognize, and the solver then used the first reference sensor alone. The choice itself is not yet saved with the model, in 5.4.180 or the preview: a reopened model goes back to the average, so pick RMS again before you send it.

A cooling unit’s set point follows its kind of sensor

A VFD set point is a pressure or a temperature. In 5.4.180, a cooling unit switched from pressure sensors to temperature sensors kept its pressure set point, so 7.473 Pa ran as a temperature of 7.473 K (−446 °F). Connecting pressure sensors put 7.473 Pa back, even over a pressure set point you had typed. The preview puts that kind’s default back when the kind changes (7.473 Pa, or 75 °F) and otherwise keeps the set point you entered.

Removed

The Energy Calculator tab

The Energy Calculator tab, and the Locale Id and Culture Id fields, are gone from Energy Calculation. Nothing on our servers reads them, and values already in a model are kept.

New

Redesigned menus

  • The menu bar is File, Edit, View, Simulation, Help.
  • File → Open Recent lists your last projects. The 5.4.180 list lost its oldest entry each time it was read.
  • Edit has Copy, Paste, Duplicate, Delete, Group and Ungroup. Anything you can’t use at that moment is greyed out.
  • View and Simulation hold the Design toolbar’s tools. Post Processing Parameters is now Simulation → Plot Setup.
  • Ctrl+O opens a project; in 5.4.180 it did nothing. Ctrl+N starts a new one.
  • Right-click Hide, Nearly Hide and Show list the object types directly, without the By Type step.

Sensor Connections for everyone, redesigned

In 5.4.180, Sensor Connections opened only in beta mode, so VFD settings sent you to a window you might not be able to open. It is now under Simulation → Sensor Connections and on a cooling unit’s right-click menu for everyone.

It lists the cooling units with a line each saying what it follows, such as “VFD · 2 pressure sensors”, and you tick the sensors the picked one reads. Ctrl-click picks several to paste sensors or VFD settings into at once. VFD Settings says which sensors the fan follows and which reading it holds, and checks the set point and airflow as you type.

A new model tree

The model tree is an outline grouped by kind of object, with a filter box, an eye to hide or show each object, and rename in place.

A Rack Builder drawn like a rack

Each rack is drawn front-on, with U1 at the bottom as on a real rack. Click or drag to pick slots, drag servers between slots and racks, and set what you picked in the panel beside the drawing. OK changes only the racks you changed, and servers keep their make and model.

A searchable Library panel

The Library panel shows a whole catalog in one list, with search across every field, filters that show how many parts each one leaves, sorting by any column, and every value of the selected part in your units.

Remove parts from your own library

In the Library panel, right-click a part, press Delete, or use the link under its name. It asks first. The library that ships with CoolSim has no remove.

Improved

Object editors open several times faster

Every field lines up in one column. On our test machine, a cooling unit’s editor took 14.2 seconds to open in earlier previews and takes 2.5 seconds now; a supplemental cooler’s took 17.9 and takes 1.1.

Tool windows ask about what they do

  • CRAC Parameter Variation has a tab for the baseline and one for each variation, each a table with a row per cooling unit.
  • Plot Setup has one Customize result plots switch; with it off, a note says which standard plots you get.
  • Energy Calculation asks whether you use measured power or estimate from a COP, and shows only that method’s fields. Other heat load is now Other power in the room, which is how the report uses it.

Smart Measure gives the gap between two things

Click two objects in View → Smart Measure for the shortest distance between them (0 when they touch), or click the room for its wall, floor or ceiling. The distance, its parts along each axis and its line in the 3D view follow as you move either object. In 5.4.180 each click snapped to the nearest box corner, so it could not measure across an aisle or to a wall, and the number stayed put when objects moved. Corner to corner is still there as a choice.

Keyboard shortcuts beside the model

Help → Keyboard Shortcuts (Ctrl+H) opens a sheet that stays beside the model while you work, and now lists the model tree, Rack Builder and Library keys. Ctrl+H again closes it.

Edit in Details

Type in any cell, or select several and set them at once. Each value is checked as you leave its cell, changes stay marked until you apply them, and closing asks before dropping them.

Add to Library says what it will do

Right-click an object and choose Add to Library. It offers only the catalogs the object fits, says before you press the button whether it adds a part or replaces one of the same name, and points to any problem at the box itself. Model names with an apostrophe work.

Power View colors racks by heat load

View → Power View colors each rack by its heat load in watts: its own, or the total of its servers, including any share to liquid. A key in the corner of the 3D view counts the racks in each band and keeps up as you edit loads; Edit range… on the key sets your own range. In 5.4.180 the color came from the watts per cubic meter of one server in each rack.

Turning Power View on and off, or saving while it is on, leaves the model as it was. In 5.4.180, turning it off made see-through objects solid, and saving while it was on stored the faded objects at 20% opacity, so the model reopened faded.

Removed library parts stay removed

Every earlier preview brought back, at each install, every part ever removed from your own library. Parts you remove in preview 5 stay removed through later updates. A part removed earlier, in your current CoolSim or an earlier preview, can come back; remove it again in preview 5 and it stays removed.

A clearer Status Report

The job’s stages show as a checklist. Stop is offered only while the job runs, asks first, and reports the stop only once our server has accepted it.

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.

Ask about a change