High rise office building HVAC question

[crollinjones]

Hello IES Gurus,
I am also working on a high rise office project. The HVAC system consists of a DOAS serving all floors. On each floor there is a VAV system serving the core part of the floor and 4-pipe fan coils serving the perimeter. The DOAS serves 2 VAV boxes on each floor. One VAV box provides outdoor air directly to the floor VAV system and the second VAV box provides outdoor air to the perimeter via ceiling diffusers (not directly to the perimeter fan coils). The two DOAS suppled VAV boxes are controlled by CO2 DCV.

I am thinking I can start with the 07i Multi AHU with DOAS. But I am not sure how to add the perimeter fan coils so that the perimeter zones are also served by the same DOAS.

Or, should I approximate the design by using two separate DOAS systems – one for the VAV system on each floor and another DOAS for the perimeter zones with fan coils?

Thank you for your great assistance!

[toemoss]

Not sure I understand your question, but I'd simplify the model by modeling a single DOAS system and model the FCU's and VAV's completely separately.
I would Simplify by delivering OA to the space even if it actually is ducted to a return.