Use the following information to troubleshoot issues with systems analysis.
When systems analysis fails, the following message is displayed at the top of the Analysis Report found in the Reports view: "EnergyPlus simulation did not generate a report for systems analysis."
If a systems analysis fails, check the eplusout.err error log located in the system temp folder.
In Windows Explorer, enter %temp% to quickly open the temp folder and search for a folder with the same name as the selected analysis workflow. Depending on your Windows security settings, you may have one more system-generated folder.
The folder path will look similar to this: C:\Users\<login>\AppData\Local\Temp\3\fbf31253-58bb-4d1a-b5db-ae57c7b3aee2\HVAC Systems Loads and Sizing. The eplusout.err log file is located in the \run sub-folder.
| Reasons for failed systems analysis | Solution |
|---|---|
|
Note that the following scenario will not generate a log file because the systems analysis failed to run. Zone equipment, such as a Constant Air Volume Box, requires an air system, but one isn't assigned.  A warning icon is displayed in the System Browser for the zone equipment that requires an air system.  |
Assign an air system to the zone equipment. See Zone Equipment. |
| The heating set point (22 degrees C) is greater than the cooling set point (21 degrees C) creating a heating/cooling paradox.
A message similar to the following will display at the bottom of the eplusout.err file: **LoadToHeatingSetPoint=-6603.432, LoadToCoolingSetPoint=-7759.433 **ZoneTempIndZnLd=32035.45 **ZoneTempDepZnLd=1156.00 **Zone HeatingThermostatSetPoint=22.00 **Zone CoolingThermostatSetPoint=21.00 Fatal** Program terminates due to above conditions. |
Assign the correct set points in the default zone and re-run the system analysis. |
| An air system is not assigned to zone equipment or zone equipment that uses an air system is not assigned to any analytical spaces.
A message similar to the following will display at the bottom of the eplusout.err file: **Fatal** Preceding errors cause termination Summary of Errors that led to program termination: Reference severe error count=2 Last severe error=An outlet node inAirLoopHVAC=" AHU-1 " is not connected to any zone ***Warning: Node connection errors not checked - most system input has not been read (see previous warning. ***Fatal error -- final processing. Program exited before simulations began. See previous error messages. |
Make sure that all air systems are associated with an analytical space. Delete any that are not used. See Air System Assumptions. |
Zone equipment that includes coils, such as a Radiant Panel, doesn't have one or more coils assigned.
 The systems analysis will fail and a message similar to the following will display at the bottom of the eplusout.err file: **Severe** <root>[Coil:Cooling:Water][RP-1-1 Cooling Coil] - Missing required property 'water_inlet_node_name'. **Severe** <root>[Coil:Cooling:Water][RP-1-1 Cooling Coil] - Missing required property 'water_outlet_node_name'. **Fatal** Errors occurred on processing input file. Preceding condition(s) cause termination. |
In the Properties palette, specify a Cooling Coil and re-run the systems analysis. |