For closed loop hydronic piping networks, Revit can analyze flow and pressure values for supply and return loops. In the model, select a pump to see the results of the analysis in the Properties palette.
A closed loop hydronic piping network must contain:
A single pump/circulator
A single source, such as a boiler
Multiple piping segments
Multiple terminals, such as radiators.
A network may contain a direct return loop or a reverse return loop.