Synopsis

This tutorial explains how to troubleshoot simple errors that may occur when exporting an ECOTECT model to EnergyPlus.

Duration

You will need about 40 minutes to complete this tutorial.

Training and Accreditation

Successfully completing this tutorial fulfills one of the practical skills required for completing Level 3 of the Thermal Analysis and Energy training module.

Resources Required

To complete this tutorial, download and open the SimpleThermalModelWithErrors.eco file found under the File Attchments section of this tutorial. You will also need to have the current version of EnergyPlus installed on your computer, and ECOTECT must configured to locate the EnergyPlus installation folder.

It is recommended that you first complete the Exporting To EnergyPlus tutorial.

Tutorial

Generating an error report from EnergyPlus

1. Open the SimpleThermalModelWithErrors.eco file in ECOTECT. The example file consists of a three zone model, but has been deliberately created with errors that will affect exporting to EnergyPlus.
   

   The SimpleThermalModelWithErrors.eco file.
2. Prepare this model for export to EnergyPlus. If you are unsure how to do this, complete this tutorial first.
3. When the EP-Launch dialogue box appears, click the Simulate button to run a single simulation in EnergyPlus. Once the simulation is complete, note that the EnergyPlus Run Status dialogue box indicates that there were 5 warning messages generated during the simulation run.
   

   5 warnings occurred during the EnergyPlus simulation run.
4. Click Ok to return to the EP-Launch window. Now click the Text Output Files button. This will open a series of text-based files, containing information relating to the EnergyPlus simulation run.
5. Look for the .err file with the same name as the original .IDF input file. This file contains a list of the warnings and errors encountered by EnergyPlus during the simulation run.
   

   The .ERR file contains a list of errors and warnings encountered during the simulation run.

Troubleshooting EnergyPlus Version Errors

1. Look at the first ** Warning ** - the stated version of the IDF file was not the same as the value expected by EnergyPlus. To remove this error message, we will need to manually edit the IDF file created from the ECOTECT model.
   

   The first error refers to a version inconsistency encountered by EnergyPlus.
2. Close the err file and return to the EP-Launch window. Click the Edit - IDF Editor button. The IDF Editor allows you to make changes manually to the input file used by EnergyPlus. It is a useful tool for making minor modifications to an IDF file created by programs such as ECOTECT.
   

   The IDF Editor application allows you to edit the EnergyPlus input file.
3. In the Class List on the left, click on the [0001] VERSION entry. To the right of the class list, you will see that the Version Identifier value is currently set to 1.4.0. Double-click in this field, and change the value to 2.1.0.
   

   Change the file version value from 1.4.0 to 2.1.0.
4. Go to the File » Save menu to save changes you have made to the IDF file. Note: This will overwrite the data contained in the original IDF file. If you want to preserve this file for later comparison, choose File » Save As instead.
5. Close the IDF Editor and return to the EP-Launch window. Check that the Input File field shows the correct filename, and then click Simulate again. This time, when the simulation run is completed, the EnergyPlus Run Status dialogue box should indicate that only four warnings have occurred this time.
   

   Only 4 errors have occurred in this simulation run.

Troubleshooting EnergyPlus Location Errors

1. Click the Text Output Files button to bring up the err file again. The next ** warning ** message states that there is some inconsistency with the Weather File and the Location object. In EnergyPlus, there is no need to specify a Location variable if a weather file has been defined, thus this entry can be deleted from the IDF file.
   

   The next warning refers to an inconsistency between the weather file and location values in the IDF file.
2. Use the EP-Launch window to open the IDF Editor application. In the Class List, select the [0001] Location entry. Click the Del Obj button to remove this entry from the IDF file.
   

   Delete the Location entry from the class list.
3. Save the changes you have made to the IDF file, and then return to the EP-Launch window and click the Simulate button. This time, the Status' dialog box should now report that only three warnings have occurred.
   

   Only 3 warning messages have been generated by EnergyPlus.

Troubleshooting EnergyPlus Geometry Errors

Correcting geometry errors between ECOTECT and EnergyPlus can be a bit tricky. This is because a new IDF file must be generated if any changes made to the original ECOTECT model after the original IDF export. And if changes have been made to the original IDF file outside of ECOTECT, the differences between the two IDF files must be merged together to create one up-to-date IDF file.

1. Click the Text Output Files button to bring up the err file again. The next two ** warning ** messages refer to InterZone Surface, or geometry errors.
   

   The next two warnings relate to problems with geometry.
2. If you have a application installed that allows you to view 3D DXF files, click the Drawing File button, and you will see that some of the wall objects have not been interpreted correctly from the ECOTECT model.
   

   If you import the 3D DXF file back into ECOTECT, you can see where one of the modelling errors has occurred.
3. To correct these errors, any zones with overlapping walls in ECOTECT need to be re-modelled as individual wall segments in order to be interpreted correctly by EnergyPlus. Open the original ECOTECT model, and make a note of the Object No for the two overlapping walls. In this model, they are numbered 21 and 23 respectively.
   

   In the original ECOTECT model, note the object identification numbers for the overlapping walls.
4. Delete these overlapping walls, and make the necessary adjustments (also make sure your material assignments are correct). Make a note of the Object No for the new wall segments. In this model, these wall segments are numbered 23, 24, 26 and 28 respectively.
   

   In ECOTECT, re-create the overlapping walls as individual segments, and note their identification numbers.
5. Save your work. Now prepare the ECOTECT model for export to EnergyPlus. Save this IDF with a different filename, so as not to overwrite the original IDF file.
6. Launch two copies of the IDF Editor. In one window, open the original IDF file. In the other window, open the new IDF file you have just created from ECOTECT.
   

   Launch two IDF editors, and open both the original and the new IDF files.
7. Start with the new IDF file. In the Class List, select the [0020] Surface:Heat Transfer entry. In the frame to the right, look at the row entitled User Supplied Surface Name. Each object will have been assigned the same number as from the original ECOTECT model.
   

   Look at the User Supplied Surface Name row - each object has the same number as from the original ECOTECT model.
8. Find the column with Obj:0023 - in this example, it is the Obj6 column. Select the entire column, and click the Copy Obj button.
   

   Select the entire column for Obj:0023 and click the Copy Obj button.
9. Switch to the IDF Editor where the original IDF file is open. Select the [0016] Surface:Heat Transfer. Click the Paste Obj button, and this new column will be appended to the end of the existing columns. Note that in the Class List, this has now changed to [0017.
   

   The copied column from the new IDF file is added to the other columns in the original IDF file.
10. Repeat these steps to bring over the other three columns from the new IDF file to the original IDF file.
11. In the Class List of the original IDF file, find the [0002] Surface:HeatTransfer:InternalMass entry. Press the Del Obj button. This removes any duplicate wall references that may cause other errors.

Delete the Surface:HeatTransfer:InternalMass entry from the Class List of the original IDF file.

1. Save a copy of the changes you have made to the original IDF file, and then close both IDF editors.
2. From the EP-Launch window, make sure the correct IDF file is loaded, and then click Simulate. There should only be one warning message reported back by the EnergyPlus Status dialogue box.
   

   There is now only one warning message reported by EnergyPlus.

Removing Erroneous Report Variables

1. Click the Text Output Files button to bring up the err file again. The final ** warning ** message states that The following Report Variables were requested but not generated.
   

   The next warning states that some requested report variables could not be generated.
2. Let's remove these report variables from the IDF file. Launch the IDF Editor, and in the Class List, look for the [0019] Report Variable entry.

Find the Report Variable entry in the Class List.

1. In the frame to the right, find and delete the entries reported as being erroneous in the err file. Select then entry, and then press the Del Obj button. There should be five in total.
   

   Delete the erroneous report variables from the IDF file.
2. Save the changes to the IDF file and then return to the EP-Launch window. Click Simulate, and there should now be no warning messages reported back by EnergyPlus. Congratulations!
   

   All the warning messages are now gone!