Netsys Chilled Water Pipe Sizing error/glitch

Hi All,

I'm trying to calculate the pressure drop for a chilled water system which starts with 250mm diameter pipe and reduces in size before it reaches the emitters.

The issue i'm having is that even though I've fixed the pipework size for flow and return as 250mm for section 1, Netsys calculates the pressure drop for this section thinking that its 150mm instead of 250mm, resulting in a massive pressure drop for this section.

I've tried deleting and redrawing the system and applying a group fix to the pipes however I keep getting the same result. Does anybody know how to fix this error?

Screenshot below.

Thanks,

J