Update family resets airflow parameter

[tbrown6608]

I have this air terminal family that I'm updating, all I'm doing is deleting one of the extrusions. When I reload into my project, all my airflows have been reset to 0! I've searched and haven't found a good solution, 1 person said to use family parameters but then I can't put that value in a tag, which I need. This must be a glitch, right? This is EXTREMELY counter-intuitive. It's the exact same family file, just being editted and reloaded, nothing with parameters is being changed at all. The extrusion I'm deleting isn't part of the duct connector or anything, just a "for-looks" piece that isn't needed.

I'm sure there's no fix for this as is usual with these types of problems. It's just how Revit works. So now I gotta go thru my entire project re-inputting all my airflows, only 130 air terminals... But hey, maybe 2016 will allow updating families without losing info... just maybe.

[chrisplyler]

Are you not getting the option, when you load the edited family back into the project, to update parameters or not?

xtn

[tbrown6608]

No, I am. I choose "Overwrite the existing version" not "... and its parameter values" but the parameter values are still changing to 0. I just tried again in a different project today and got the same thing.

[chrisplyler]

Very wierd then. Sorry, that's all I could think of. Hopefully somebody else might have an idea.

xtn

[tbrown6608]

Yeah hopefully, thanks for trying tho. The weird thing is, I would think that if 1 parameter value is being reset then they all would, but its only resetting the airflow value. The shared parameters I'm using to designate (which are just text parameters) are keeping their values. Maybe it has something to do with the type of parameter the airflow is... which is an air flow parameter. Idk, just gonna keep trying to avoid the need for updating families for now.

[chrisplyler]

I just tried it with a supply diffuser in a project I did a few months ago. Selected one, edit family, select and delete an extrusion and even a couple of model lines, reload into project, and the Flow parameter didn't change.

I even experimented with changing the MaxFlow and MinFlow of the connector in the family to a range that doesn't include what I've set the Flow value at in the project, reloaded WITH parameter values, and it still doesn't change the Flow value I've set.

Something is definitely not right for you.

xtn

[tbrown6608]

I just created a new project, placed an air terminal (which defaults with an airflow of 500), I changed it to 200 CFM, editted the family, reloaded and it didn't change anything, the arflow was still 200. Then I connected the air terimal to a duct which placed it on a system, did the same thing and the airflow changed to 0, which isn't even the default value, 500 is.

Was the family that you editted connected to a system? Really hoping its not my families...

[tbrown6608 · Accepted solution]

AH HA! So i just changed my family's duct connector calculation to be "preset" instead of "calculated" and now when I reload the airflows aren't lost. So yeah, no idea what the calculated option is supposed to do but it wipes your airflows. Now to go thru my template to fix all those connectors.

Thanks for the help, even if you didn't exactly lead to me this, you kept me at it, haha.

[tbrown6608]

And by "my family's duct connector calculation" I mean "my family's flow configuration", in case anyone done got confused.

[chrisplyler]

AHA! Good detective work!

[chrisplyler]

...And yes, the terminal I experimented with was/is connected to a system. If I change the Flow for it, the ductwork and equipment upstream correctly recalculate.

xtn