Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
You are missing the Terminals between the Zone and the Splitter. See picture below. You probably want AirTerminal Single Duct Uncontrolled terminals for this type of system. Also, I'd imagine that you'll need heating/cooling coils and a setpoint manager on the air loop as well, but those aren't the cause of the error you asked about. 
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