My building type directs me to use System 4 - Pkgd DX Heat Pump with electric supplemental heat for the baseline system. The LEED building is in climate 2A, hot and humid OA conditions. The proposed system is a dedicated 100% outdoor air unit supplying neutral ventilation air (~70F) to many split-system DX heat pumps. This is a common strategy to dehumidify ventilation air in this climate zone.
1. How does System 4 treat outdoor air in the baseline system? Does it not allow me to model a 100% DOAS with electric reheat?
2. Or do I have to model individual packaged rooftop heat pumps with a percentage of outdoor air? With this percentage of outdoor air, the heat pump compressor would have to operate to dehumidify, and then may need to use the electric reheat to maintain space temperature.
I have seen other posts stating that the baseline system may not make "design sense", but I just wanted a confirmation/clarification.
I appreciate the help, thanks!