Problem

When attempting to compute a model when using the HEC-22 Energy loss method used in one or more nodes, the following error message occurs: "Object reference not set to an instance of an object."

Solution 1

This message has been known to occur if you are using the HEC-22 Energy headloss method without also assigning a benching method. You can confirm that the benching method has been assigned by opening the node flextables and looking at the Benching Method column. If this field is blank, assign a method to it.

If this is the cause of the issue, then a different headloss method could be used instead, such as Standard or Absolute.

Solution 2

Check all input data and make sure all values are entered and are reasonable.