Air terminals use connectors that have their Flow Configuration parameter assigned to "Preset". This means that the user assigns a specific flow value, such as 150 cfm.
The VAV needs to have the connector that supplies air to the air terminals (diffuser) set to a Flow Configuration value of "Calculated". This allows all connected air terminals flow settings to accrue to the VAV. The Single Duct VAV family has the correct Flow Configuration settings but the connectors are linked.
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