RapidBalance 4.0 could be downloaded from the developer's website when we last checked. We cannot confirm if there is a free download of this software available. The actual developer of the free program is Honeywell Inc. The most popular versions of the tool are 4.0, 3.0 and 1.0.
We recommend checking the downloaded files with any free antivirus. RapidBalance is included in Internet & Network Tools. The most frequent installation filenames for the software include: RapidBalance1.exe, RapidBalance2.exe, RapidBalance2_2.exe, RapidBalance3_0.exe and RapidBalance3_1.exe etc.
From the developer:
The intended usage of Rapidbalance is for calibrating installed VAV box controllers and to verify that the VAV box airflow meets the design specifications. This application is free to the general public to download. Stand-alone, laptop PC-based software program. Easy to use, intuitive tool for VAV balancing. Ability to drive multiple VAV’s to max or min flow setpoint
You may want to check out more software, such as PageScope Network Setup, Veeam FastSCP or CrossFTP Server, which might be related to RapidBalance.