Autodesk Revit MEP

[#1]

Does Revit MEP track flows throught flex pipe?  I'm working on a project and have started to hook-up the hydronic unit heaters.  I thought I'd be able to flex from the mains but it doesnt' seem to be working.  If I "hard pipe" to the connectors on the unit, flow is transfer from the assigneed valve at the unit to the assocated piping network but not it the connection uses flex pipe.

Anyone else experience this, thoughts as to what I may be doing wrong?

Thanks in advance.

[#2]

Make sure your system is consistent throughout the 'network'... i.e., check each element's System Name... if they are different for any reason, this is indicates a discontinuous network, which will halt flow.

Refer to attached image... flow seems to work as expected through the flex.

Perhaps you can provide a simple model / exmple demonstrating the problem?