To the first question: yes, split the zone
To the second: if I remember correctly, yes, you can.
ÂDear EPlus Group,
Is it possible to model more than one VRF indoor units in the same zone? My case is a big laboratory space served by three VRF indoor units with the same outdoor condensing unit. Can I use ZoneHVAC:EquipmentList to add similar TU system? Or should I divide the zone into smaller zones representing an imaginary zone served by each indoor unit and connect all three zones with voids?
Second question, is it possible to link the supply air from secondary outdoor air system (DOAS) into each VRF indoor unit's mixer rather than directly blown into the zone? Presumably by defining ZoneHVAC:EquipmentConnections and tweaking OutdoorAir:Mixer?
Any help would be greatly appreciated,
Regards,