Duct, Piping and Equipment Randomly Moving

[ambernwood]

I have been having problems with equipment, ductwork, and piping randomly changing elevations and locations in the model.  I am using both Revit MEP 2013 and Revit MEP 2014 and have had this problem in both version.  Currently this has created a huge problem with clash detection.  One time everything is clash free.  The next time I get into the model it is not clash free. One example is I've had pipes go from being in the ceiling to being located on the floor among many other problems. 

Has anyone else run into this problem and/or come up with a solution or best practice for keeping this from happening? 

I was thinking about pinning objects but I am worried about overconstraining the model and/or making the file size huge.  Any advice would be hugely appreciated.

[CoreyDaun]

There has got to be something that is triggering the change, be it another user (inadvertently) in a Workshared Project or the Level changing as a result of an update with the linked architectural model.

If you cannot identify the cause, then perhaps try pinning some of the Pipes that have been changing, and see if that helps. And regarding the file size, you can test this by opening your Project file with the 'Detach from Central' option, pinning all of your elements, and the saving it somewhere to see the new file size.