8.4.5. System balancing options<br>

### 8.4.5. System balancing options

System balancing options also include control of the sizing of the required available pressures for pumps and sources. The tab includes the following fields:

- Resize pumps on pipe-runs – enables pump sizing during current calculations; when a project is calculated for the first time this option is enabled automatically.

- Retain user specified Hpump on pipe-runs – when pumps are sized their delivery heads specified in the editor are retained; when this box is not checked, the delivery heads are deleted, as if “?” was entered as the delivery head in the editor.

- Allow larger diameter of DP valve – when this box is checked a pressure differential valve may be sized with larger diameter than the calculated diameter of pipe-run on which it is installed.

A table specifying the following minimum pressure drops is displayed below:

- on each terminal unit and its fittings,

- on each control valve (except for those assigned to the first group – on terminal units),

- on each pressure differential valve.

These values may also be specified for each individual valve in the graphical editor.

Fields displayed below enable specifying the available pressure drop for each source in the project or indicating that they should be determined automatically. You can also specify in advanced options for each source whether excess pressure is to be throttled by means of valves near the terminal units or near the source (if there are more control valves between source and terminal unit).