The size of the network exceeds the current limit for flow/pressure analysis. In the Mechanical Settings dialog, under Pipe Settings - Calculation, disable the option to Use analysis for closed loop hydronic networks.

public static FailureDefinitionId NetworkErrorModelTooBig { get; }

Public Shared ReadOnly Property NetworkErrorModelTooBig As FailureDefinitionId
	Get

public:
static property FailureDefinitionId^ NetworkErrorModelTooBig {
	FailureDefinitionId^ get ();
}