Stratified water heat autosize options causing program crashes

Issue overview

The EnergyPlus program may crash when the stratified water heat tank inputs are set to autosizing some input parameters such as tank size and height. The issue can be demonstrated by the attached .idf file which is slightly modified from the example file 5ZoneWaterSystems.idf: in the file a stratified water heater replaces the original mixed water heat in the example 5ZoneWaterSystems.idf file.

The temporary workaround is either switching to a mixed water heater (WaterHeater:Mixed), or setting the stratified tank size and height values manually.

Details

Some additional details for this issue (if relevant):

• Platform (Operating system, version): All
• Version of EnergyPlus 9.3-9.4
• Helpdesk ticket number 15592

Checklist

Add to this list or remove from it as applicable. This is a simple templated set of guidelines.

• Defect file added (list location of defect file here
  5ZoneWaterSystems_changed_to_stratified.zip
  )
• Ticket added to Pivotal for defect (development team task)
• Pull request created (the pull request will have additional tasks related to reviewing changes that fix this defect)

Start by reproducing the crash with the attached 5ZoneWaterSystems_changed_to_stratified.idf file, using EnergyPlus 9.3 or 9.4, and compare it with the original example and the manual-size workaround. Trace the stratified water heater autosizing path for tank size and height. Done means the example runs without crashing when those fields are autosized, with a regression check covering the defect.