The System Parameters dialog works with ‘managed systems’. A managed system has a system frame and a multiplexed set of zones and related components and controllers.
Each managed system in the ApacheHVAC file has a System Parameters dialog that provides a user-friendly means of editing and in many cases deriving its component level parameters; with user inputs alongside zone loads, sizing parameters, derived values, and engineering checks.
While the entire system must be contained within the system frame, it can be connected via airflow paths to other systems, which may or may not also be managed systems. However, only the components and controllers within the system frame can be linked to the System Parameters dialog.
The System Parameters dialog is accessed either by double-clicking top bar of the system frame or by clicking the System Parameters toolbar button shown above, and then selecting the ‘System to edit’.
System frame
The system frame is a container, a clickable element, and a means for providing feedback. The system frame changes color, has symbols added or removed at the right end of the top bar, and provides ToolTip information to indicate the current status of the system with regard to user edits, autosizing, and error conditions.
Summary of System Frame Status and ToolTips
User action or trigger
Frame, top bar, and text color
ToolTip
System unchanged from HVAC library; no user edits or autosizing.
“HVAC network unaltered since being loaded from system or user HVAC systems library—no user edits or auto-sizing yet”
User edits have been made and saved, but not yet assigned.
“User edits have been saved, but not assigned to the components and controllers in the HVAC network.”
User edits completed and assigned to components and controllers.
“User edits have been saved and assigned to the components and controllers in the HVAC network. If previously auto-sized, at least one or more auto-sized value has been overridden by a saved user edit. Unaltered auto-sized values remain in green text.”
Error condition in System Parameters; must be corrected before assigning.
“There is an error in a user-edited value or derived parameter. This error is highlighted in the dialog and must be cleared prior to the Assign operation or any simulation of the HVAC system”.
List of the parameters in error is provided following this text.
Zone-level sizing has been completed and assigned/updated (auto or manual).
“Zone-level auto-sizing has been completed and sized values have been assigned to components and controllers in the HVAC network.”
Zone-level sizing or Zone- and then System-level sizing has been completed but not assigned/updated either automatically or manually.
“Zone-level autosizing or zone- and then system-level autosizing have been completed, but sized values have not been assigned either automatically (via the ASHRAE Loads interface) or manually.”
Zone-level sizing has been completed & assigned, but subsequent edits have not been applied to the components and/or controllers.
“Zone-level sizing completed, but revised data associated with subsequent user edits has not been assigned. System-level sizing, if previously completed, will need to be re-run to account for changes.”
System-level sizing completed, but zone-level sizing for this system has not been completed (e.g., if intentionally set up and sized manually at zone level, then auto-sized only at system level for coils, fans, and plant equipment/loops).
“System-level autosizing have been completed and applied, but zone level autosizing has not.”
Autosizing at zone and system level have been completed and values assigned to components and controllers.
“Both zone- and system-level auto-sizing have been completed and sized values assigned to components and controllers in the HVAC network.”
