Occasionally, simulations will encounter errors without the EnergyPlus Troubleshooting panel. This indicates some project geometry conditions are responsible. Example project geometry conditions are listed in this article along with the solution for them.
Check 1: Room or group of rooms are completely enclosed by other room
How to identify:
This condition is typically found with corridors where a room or set of rooms is enclosed by another room. This can error out the simulation because EnergyPlus is unable to set boundary conditions properly.
Steps to correct:
Simply, break the corridor or encircling room so that no single room encloses others. Here is an example using air-walls.
Check 2: Tiny walls or endpoints that are not part of any room
Endpoints without walls can cause the simulation to fail by creating slivers and surfaces that only have two vertexes.
How to identify:
To find these types of endpoints turn on the Endpoint Snap
Next, turn on the wall mode to display all the endpoints within the project
Endpoints that are not associated with a wall will need to be deleted
Steps to correct:
These endpoints can be removed by extending the wall they are trying to create and then deleting them. In order to select these endpoints follow these steps:
Turn off the Visibility of Floors
Use Shift drag+click to select the area around the extra endpoint
Next, select and drag the problem endpoint to create a full wall
Delete this wall
Check 3: Internal walls not defining a Room
How to identify:
Wing walls or disconnected walls can cause issues in OpenStudio related to the vertex. Importantly they will have essentially no impact on the loads and for best success should be removed.
Steps to correct:
As noted, these walls be removed without impacting the load results
Alternatively, if a room is meant to be defined, adding the missing surfaces will also correct the potential issue
Check 4: Look out for overlapping windows
How to identify:
Tap on the '3D' button at the top bar in the drawing.tool. Here's a great article to refer to understand the drawing.tool interface.
Steps to correct:
Delete the overlapping windows by simply selecting the window and clicking on the 'delete' keyboard button.
Alternatively, the orange windows can be moved until they do not overlap with other windows.
Check 5: Sliver Rooms
How to identify:
Sliver rooms or very thin void rooms cause issues within the EnergyPlus engine due to vertex oddities. These also can impact the load incorrectly as loads that are per area may be over-estimated.
Attached below is an example of a sliver room
Steps to correct:
A single wall should separate the two rooms. The corrected sample is provided below
This simplified the model to optimize the run time of the simulation.
Check 6: Extra Vertex in Walls
How to identify:
Extra nodes or vertex can be created during an import or while drawing walls within the tool. When drawing the walls and deleting we can sometimes see that a leftover
Steps to correct:
Remove the extra vertex to make it a single wall by single-clicking the endpoint icon (blue circle)
Important Note: This case will not always fail, however when it does the warning will be related to vertex mismatch.