Issue overview

Unmet Hours post describes a user trying to use Energy Management System (EMS) feature of EnergyPlus to dynamically change the construction assembly for a surface. They are modeling phase change material (PCM), which requires using the Conduction Finite Difference (CondFD) algorithm for heat transfer (set via HeatBalanceAlgorithm object type). However, they are seeing the following error message:

** Severe ** InitEMSControlledConstructions: EMS Construction State Actuator not valid.
** ~~~ ** Construction named = WALLPCMEXTERNAL has number of finite difference nodes =10
** ~~~ ** While construction named = SISOPEN has number of finite difference nodes =0
** ~~~ ** This actuator is not allowed for surface name = SIS, and the simulation continues without the override

'SIS_1.idf': original file from Unmet Hours user, yields severe error above
'SIS_2.idf': original file from Unmet Hours user, yields severe error above
'SIS_2-test-SISOpen.idf': updated test that uses EMS to always assign construction assembly named "SISOpen", a "normal" assembly without PCM, no severe error
'SIS_2-test-PCM.idf': updated test that uses EMS to always assign construction assembly named "WallPcmInternal", an assembly with PCM severe error, but it's reported TWICE and now comes BEFORE the " ************* Beginning Simulation" line in the error file instead of after

Operating System (Multiple choices)

Any

Operating System Version

Any

Version of EnergyPlus

25.1, 23.2

Unmethours link or helpdesk ticket number

https://unmethours.com/question/101164/issue-with-ems-construction-state-actuator-and-finite-difference-nodes/

Defect file

SIS_1.idf.txt

SIS_2.idf.txt

SIS_2-test-SISOpen.idf.txt

SIS_2-test-PCM.idf.txt