Netsys doesn't seem to be adding cumulative flow rates correctly

Hi. I am using Netsys to design the cold water system for an industrial site. When I run the calculation it does not achieve the sum of the outlets. I've narrowed this down to two places where the components when added mathematically are greater than the flow rate produced by Netsys. The screenshot below is one of the problem areas. I would have expected the flow rate on the left to be:-

8.151 + 0.269 = 8.42 l/s

(Netsys figure is 8.19)

Thanks

Stewart Bullock