I am modelling VAV system.
When I check the System Ventilation Requirements for Cooling from html table result, percentage of outdoor air to supply air is not 100% (for example, VAV 1F has 43% outdoor air fraction compared to total supply air in the air system) as shown in image above. However, when I look at hourly data, Outdoor Air Fraction is 100% anytime when the air system is operating as shown in middle image. This lead to additional outdoor air intake more than required(e.g. in summer, outdoor air volume is more than 5kg/s which is much bigger than 2.15m3/s summarized in System Ventilation Requirements for Cooling as shown in bottom image)
I want to keep outdoor air intake to minimum requirement. Does anyone know how to achieve this?
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