Revit MEP 2013, Duct Pressure Loss Report, System doesnt show in System Selector

[agobel]

I am trying to get a static pressure calc on a return duct system consisting in of return diffusers and a return fan.  I can get the system to add the flow and all diffusers are set to static pressure "specified" with a value.  The system doesnt show up in the Duct Pressure Loss Report - System Selector and the system static pressure reads "not calculated"  even though the Return Air system is set to calculate.  I do recieve an error on the system indicating that the system is "not well connected" even though there are no open ends on the system and I have flow calculations thoughout all of the ductwork. 

Am I missing something?  Is the system not showing in the system selector because it say that it is not well conneceted?  If thats the case is there an easy way to make the system well connected even though it already appears that it already is?

Thanks

[Chris.Aquino]

I would check the flow settings on any equipment on the system.

I would review the following posts:

http://inside-the-system.typepad.com/my_weblog/2007/11/go-with-the-flo.html

http://inside-the-system.typepad.com/my_weblog/2007/12/go-with-the-flo.html

http://thebuildingcoder.typepad.com/files/me204-3_connectors_in_revit_mep_content.pdf

[maryko]

I had the same problem, and this is how I solved it:
I went to system browser and under "Mechanical" systems, found my desired system but by right clicking on that system I found that "Divide system" option is active, meaning that I had missed some parts disconnected. So I divided the system into 2 parts and then I became able to do the "Duct pressure Loss" analysis.

[magnolouis]

Hi Chris,

Thanks for sharing this things its really helpful, its just recent I got my head into RMEP calculations and I just want to ask what is your stand in the case study/report from the link attached.

http://www.ce.utexas.edu/prof/Novoselac/classes/ARE389H/Handouts/Old_Projects/Comparison%20of%20Revi...

Thanks and Best Regards..