Designing and optimizing HVAC systems requires the ability 'to play' with the design parameters. The Hysopt software includes powerful tools to access and change the systems' design parameters in a fast and synoptic way. 

Parameter box

When left clicking on a basic circuit a parameter box appears on the left side of the canvas in which the parameters of the respective basic circuit can be modified. For basic circuits containing multiple hydraulic components, the parameters are arranged according to the respective components. If not all parameters are shown (in case of a large number of parameters) you can scroll down in the parameter box using the mouse wheel.

The selected basic circuit is marked green in the drawing canvas.

1. Parameter box of the selected basic circuit
2. Different component within the basic circuit

Locking parameters

The Hysopt software calculates the optimal system parameters. However, as a designer you are always able to change parameters as you like. By clicking on the lock icon a parameter can be forced to a user defined value (the lock icon is marked in red). This way the software sees this parameter as a hard input value instead of an (optimized) calculation result. This feature is particularly useful in renovation projects where the existing parts of the system must be modeled 'as is' by locking the parameter values. 

Note that parameters without lock icon are always input parameters specified by the designer, if not the presented default values are used . E.g. the minimal valve authority is not a calculation output but a user defined requirement.

Note that when several basic circuits are selected (see 'Changing parameters for multiple basic circuits'), the lock icons can be marked grey, red or orange:

• A grey marked lock icon means that the parameter value is unlocked
• A red marked lock icon indicates that the parameter value is locked for all basic circuits within the selection
• An orange marked lock icon means that the parameter value is locked for some of the basic circuits within the selection

Changing parameters for multiple basic circuits

In order to easily modify system parameters in large systems (e.g. for sensitivity analysis), parameter values can be changed for multiple components at once:

• using 'Alt+Cick' within one canvas
• using 'Shift+Alt+Click' to span multiple canvasses
• using a drag selection

Using 'Alt+Click' within one canvas

When pressing the 'Alt' button while clicking on a basic circuit (or pipe), all basic ciricuits of the same type will be selected at once. The number of selected basic ciruits is shown at the top of the parameter box. Uniform parameters (parameter values are the same for all basic circuits in the selection) are marked in black whereas a red marked parameter value indicates that different parameter values are applied within the selection. When overwriting a red parameter value, the new parameter value will be marked in black which means that it is a now a uniform parameter value. 

In the example shown below, all radiators are selected at once by using the 'Alt-Click' selection. The total number of selected radiators (5) is shown at the top of the parameter box. The temperature regime 70/50/20°C and the Kv value are marked in black as the same values apply for all five radiators. The design heat flow is marked red as the selected radiators have different values for this parameter.

1. Number of selected basic circuits

Using 'Shift+Alt+Click' to span multiple canvasses

The 'Shift+Alt+Click' selection is basically the same as the 'Alt+Click' selection however it spans multiple canvasses (see 'Canvas Management') whereas the 'Alt+Click' selection is restricted to the canvas which is currently shown. To make the designer aware of the fact that the 'Shift+Alt+Click' selection spans multiple canvasses, the heading of the parameter box is shown in pink.

Making a drag selection

A drag selection can be made by dragging the mouse cursor over the desired area in the drawing canvas while pressing the left mouse button. During the drag selection movement a dashed line rectangle indicates the selected area. After the selection, the selected basic circuits are marked green and the respective basic circuits are listed in the parameter box. The respective parameter value appear when clicking on the name of the basic circuit.