OpenStudio Convergence Error

asked 2021-06-03 15:41:12 -0500

Draza gravatar image

updated 2021-06-04 13:37:23 -0500

I'm working on a project for school using OpenStudio and am receiving several errors stating that the model failed to converge for several of the thermal zones. I have read through the existing questions of other users having a similar issue, but can't seem to find detailed information on what causes this issue. I'm assuming that if I increase the maximum number of warmup days or the tolerance values that I will be able to solve some of the convergence issues, however I'm not sure what values are considered acceptable? I added the "Add Output Diagnostics" reporting measure to my model and used the "reportdetailedwarmupconvergence" input value, but it didn't seem to add any further information to the eplusout.err file. Any help regarding this issue would be much appreciated. Here is a link to the model. Thank you

EDIT: The model converges in less than 10 days when using ideal air loads. Does this mean that the convergence issue is caused by the HVAC system that I have assigned to the thermal zones? I'm using a VAV reheat system with district heating and cooling.

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The first thing I would loo for is excessively large internal loads. What is the source of the internal loads in your model, and what is consumption for electric and gas plug loads? Another thing to look at would be the weather file if you are using a custom weather file.

David Goldwasser gravatar image David Goldwasser  ( 2021-06-06 14:48:16 -0500 )edit