Aux Vent. System

[Jonnymac]

I am trying to get my head around the "Aux Vent. system" feature.

In what instance would this be used? Is it for when you have two heating/cooling systems which work independently of one another, if so how is this controlled? Or is this the best way to assign a tempered/Trim air AHU system that is supplying ventilation to spaces, but not conditioning the space?

If there is any user guides or videos on this it would be much appreciated. I have covered the training some time ago, but I cant remember what was discussed on this topic.