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Bug in phase change modelling

I have a wide experience on phase change modelling but a few experience using EnergyPlus. I am trying to run the BESTEST case 600 with a PCM replacing the fiberglass quilt. To this end:

1) I took the Case600.idf from the ANSI/ASHRAE Standard 140 - Input Files - v8.0 (http://energyplus.helpserve.com/Knowledgebase/Article/View/128). 2) I update it to run EnergyPlus V9.5 using the IDFVersionUpdater. 3) I replace the original HeatBalanceAlgorithm by ConductionFiniteDifference. 4) I replace the fiberglass quilt material properties by those of the considered PCM, adding an enthalpy table using MaterialProperty:PhaseChange. 5) The resulting IDF file, Case600_ENT.idf, was run for Golden (CO, USA), and the run was succesfully completed.

After that, I define Case600_NOENT.idf, identical to the previous one except for the elimination of MaterialProperty:PhaseChange. So, this new material has no latent heat.

Surprisingly, both cases gave identical results.

I found a similar question 4 years ago (https://unmethours.com/question/21828/unchanging-surface-temperatures-despite-change-in-phase-change-temperatures/), but it remais unsolved.

I would really appreciate your help to find the bug.

Bug in phase change modelling

I have a wide experience on phase change modelling but a few experience using EnergyPlus. I am trying to run the BESTEST case 600 with a PCM replacing the fiberglass quilt. To this end:

1) I took the Case600.idf from the ANSI/ASHRAE Standard 140 - Input Files - v8.0 (http://energyplus.helpserve.com/Knowledgebase/Article/View/128). 2) I update it to run EnergyPlus V9.5 using the IDFVersionUpdater. 3) I replace the original HeatBalanceAlgorithm by ConductionFiniteDifference. 4) I replace the fiberglass quilt material properties by those of the considered PCM, adding an enthalpy table using MaterialProperty:PhaseChange. 5) The resulting IDF file, Case600_ENT.idf, was run for Golden (CO, USA), and the run was succesfully completed.

After that, I define Case600_NOENT.idf, identical to the previous one except for the elimination of MaterialProperty:PhaseChange. So, this new material has no latent heat.

Surprisingly, both cases gave identical results.

I found a similar question 4 years ago (https://unmethours.com/question/21828/unchanging-surface-temperatures-despite-change-in-phase-change-temperatures/), but it remais unsolved.

I would really appreciate your help to find the bug.