Wow. To start off I want to say how disappointed I am that I cut off the last module a minute short. In this one minute, which I watched after I "finished" my model, Glenn says if your building is large, to only do a section to the best of my ability. Well, I ended up doing the whole building and felt the frustrations of all the small nuances of modeling an HVAC system.
In creating my HVAC system, I felt that the general ideas and thinking were there, but reflecting them within the model was nearly impossible. I recognized that my building could be broken up into a few different zones: south, common spaces, work spaces, and miscellaneous (bathrooms, storage, mechanical, etc). With this system I was able to create an air flow system, and I like this system more because it is more efficient and allows for the most flexibility. Since my climate is cold but with warm summers and without dry seasons, I could not have a passive heating system. Therefore, I focused on a localized mechanical room that could distribute air through an air handler. From here, I could accurately distribute the necessary cFm needed within each space. Similarly, with the cooling system, I utilized a similar method as my heating. I had a ton of specific challenges with my HVAC system but most are to do with the nuances of modeling. My big issue was that I have 0 prior experience with HVAC, so I had to watch pretty much every module and video to learn and craft something that I could actually work with. It's far from perfect, but it's a start and a worthwhile system for it being my first one.
*Quick note, this is my second floor model, but the first floor is very similar with some minor changes to my return airflow system.