How is volume flow rate calculated in Netsys?

Thomas - you need to consider that there will be mains losses - or possibly gains with CHW - to consider as well.

This document explains this process.

Regards,

Thanks for your quick response again Duncan.

Yes so wouldn't the figure be larger not 10% smaller?
How does Hevacomp calculate the volume flow rate?

Thomas - the example in the document is showing a heating system where you are likely to lose temperature through the mains. In a chilled water system you are likely to gain temperature through the mains, which would show the reverse of what the document shows.

The document explains the methods used for volume flow rates.

Regards,

Thom - Further to the comment above

Can you let me know your flow and return temperature at the system marker, and also the surrounding temperature that is set for the project?

Regards,

Flow temp: 4.8
Return temp: 13.2
Surrounding temp: 25

Thomas - I think I'd better take a look at the project. Can you PM me so we do that?

Thomas - I think I'd better take a look at the project. Can you PM me so we do that?

For reference, the issue here was misinterpretation of data. Thomas was using the emitter schedules to derive the total load from the emitters on the layout, but wasn't aware that the emitter schedules include all emitters on a floor even if they are not connected. Checking the data showed that a number of emitters where placed in isolation and not connected to the system. This accounted for the (approximately) 10% difference in results and expected results. In this case mains losses were so small to have a negligible effect.