The Classification property identifies a type of mechanical equipment family.
The Classification defines a list of behaviors that drive which process(es) a particular component provides. The Classification also determines how calculations are performed for hydronic piping networks.
Currently, Pump is the only Classification in use. Pumps have two built in parameters: Calculated Flow and Calculated Pressure Drop. Set the Classification on a pump to enable the Calculated Flow and Calculated Pressure Drop properties for the entire network.
You must enable analysis for closed loop hydronic piping networks on the Hydronic Networks tab in the Mechanical Settings dialog. See Specify Calculation.