It seems that the duct radius splitter (duct fitting) object works in a weird manner.
The two branches do not recognize the systems other than the Fresh Air default system. The main duct on the other hand works properly.
Does it happen to you too?
I'm in the INT version, latest hotfix.
Operating system used: Windows 11
eng. Alessandro Mandala - Italy
AC27 latest hotfix
Win 11 Pro 64bit
Ultra 9 275HX 64GB GeForce RTX 5070ti