After inserting a valve, it does not appear in the 3D view. There is blank space where the valves should be. 

When printing final, your outside hose demand after the pump isn't included in the total flow.

In the example above, the system demand is 1274 gpm is represented by point D2/D3.  The outside hose adds up to another 250 gpm but there isn't another marker at 1524 gpm

*Please note, while the Demand summary at the top shows D3 as a point, since D2 and D3 are the same value, the graph will only show point D2.

Primary calc results are shown, and when selecting OK to continue back to the calc input screen, the two messages below are displayed, twice;

"The designated source node was not found in the list of pipes" OK

"Calculation failed for an unknown reason" OK

Process Error Hydcalc

When trying to insert a valve type fitting from the parts tree, you get the error; 

Still!!! Block ### is missing.  Please insert manually.

However checking the database for the drawing file shows it exists.

All building dimensions are inserted into an different layer than the current one.

No connectable heads found within distance specified for the line

illustrated, or heads were already connected ...

No connectable heads message comes up, even when there are obviously heads that can be connected. Can also be error stating Please re-select line away from other lines

In Navisworks 2024.2 to Navisworks 2025.3 (possibly a sub-version earlier or later), Properties for appended HydraCAD persistent models do not appear, and a Proxy Object notice is given.

"AutoLIST Failed!... Please run Listing CheckUps"

This message is shown when running the AutoLIST process, but checkups didn't find any errors AutoLIST Failed

When opening HydraCAD, you get this error

Unhandled Exception...DAO32Server...

HydraLIST ribbon is missing in the Revit toolbar when opening a project file.