Synchronization Serious Problem

[Powerian]

Dear All,
I am suffering from a very serious problem with my Revit 2015 model.
I am working with a team on a central file. The project consists of Basement + Ground + 1st + 2nd floors, each is about 6000 sq. m.
The problem I have is with the HVAC model. When one of my team synchronizes his local file with the central file, a lot of air outlets are disconnected from the ducts (randomly).
Kindly deal with this post as an urgent issue. Your soonest reply is highly appreciated.
Thanks in advance for your valuable attention.

[Brian Myers]

Are the air outlets hosted to the architectural? I am wondering if the changes he is making to the model are forcing the outlets to adjust and then become unconnected? If that's the case, you may need to either have them hosted to a different element or leave them unhosted. Most likely, hosting them to a reference plane (as an example) would help, but could take some time to do.

[neightyeight]

When you say "disconnected" what do you mean exactly.

Is the air device moved so that the duct routing no longer works and thus Revit will want to delete that interconnecting ductwork? If so the earlier post may have identified the issue.

Is everything in the right place but the air device is no longer connected to the ductwork such that when moving the ductwork the air device is left behind. Essentially is the air device no longer "physically" connected to the ductwork? If so I would lean towards a problem with the air device family and specifically the connector within the family.

Is Revit just giving you a "Elements are disconnected" warning? The software will give you that warning from time to time but everything is actually still connected just fine.

Is this happening to air devices that are attached directly to the side of a piece of ductwork? This option in Revit allows you to place an air device with a tap and a little strip of duct between the duct main and air device. It works well enough but I have had problems with the air device moving unexpectedly when adjusting/stretching the duct main. If so try using the old method of creating that little strip of ductwork tapped into the main with the air device at the end.

Lastly, is the logical system still intact? If you click on the air device and choose the "Edit System" button does it see this air device as part of a logical system including a piece of equipment and likely several other air devices? If so is it even on the correct system? Occasionally I've had users in our office that will draw a piece of ductwork on the outside air system into a supply diffuser, which is fine if you want it to be part of the outside air system but is not if you want it to be part of a supply air system. Later they try to correct this issue by just changing the duct's system to supply. The problem is the air device is still "forced" onto the outside air system and can't be changed unless you first disconnect the ductwork, choose the air device and choose edit system, remove that air device from the system (this often results in the logical system being deleted since only that air device was on that system), then re-attaching the duct to the air device, which will then become part of that duct's system.

Hope one of those helps!