Revit MEP model Text question

[revitworkbench]

Hi, I have a duct fitting that I want to write some parameters on its side using model text. I there are two types to this fitting. I went into the parameters editor, found the parameters I wanted, in both types, typed in the value I wanted, then went to the fitting, placed the model text and associated it to the parameters I wanted. Now everything seem so work just fine in the family editor, and I get no errors, however when I export and overwrite into the project, I get this error message: "This field cannot be blank. Enter text to continue." and it wont even let me try to change the instance parameters. Any idea what is going on?

[CoreyDaun]

Are you referencing a System Parameter (i.e. Comments) or a Parameter that was already part the Family when it was in the Project for the Model Text? The problem is that Model Text cannot be blank, so if any of the values for the controlling parameters in the Project are blank, this error will be returned. You may want to try choosing to overwrite the Family but opt to also overwrite the parameter values.

[revitworkbench]

Yeah, I think that is my problem. I do choose to overwrite the family and its parameter values. but it is acting like it is not over writing them. To verify this. I simply deleted all the instance in the project and tried loading the family again and it seemed to work. But thats kind of an extreme solution if you catch my drift. I double checked all the parameters that are called by the model text and they are all filled. I dont understand why this is happening.

[CoreyDaun · Accepted solution]

I will go kinda confidently out on a limb and say that one or more of those Text Parameters controlling the Model Text is an Instance Parameter. When you choose to overwrite the existing parameter values, that only applies to Type Parameters, since the Instance Parameters in the Family are simply default values, which is why their names are followed by "(default)". There's not much of a solution here, aside from do what you described or creating a brand new parameter.