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Coil limit per HVAC loop

asked 2015-05-05 14:17:52 -0500

updated 2015-07-11 17:27:03 -0500

I've read multiple places that EnergyPlus has a default limit of 50 coils per HVAC loop, but this limit can be increased (I believe in the .IDD file). Can anyone share exactly where this limit can be increased/removed?

I'm assuming this will impact run time; are there other significant stability or performance issues to be aware of?

Thanks for the insight.

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You can find here how to adjust idd file to lift the 50 coils per loop limit.

Ivan Korolija's avatar Ivan Korolija  ( 2015-05-05 14:22:25 -0500 )edit

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answered 2015-05-05 14:29:47 -0500

Certain IDD objects have extensible fields that have artificial limits. The ones that come to my mind as pertinent are

  • Branch
  • BranchList (If you have a large number of parallel branches)
  • ControllerList (If the coils are water coils)

There might be others that I forgot, but that will probably get you going.

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@Kyle Benne is the OpenStudio IDD contained in a separate file from EnergyPlus? Is this also editable?

jmcneill's avatar jmcneill  ( 2015-05-05 15:06:59 -0500 )edit

Yes OpenStudio has a separate IDD supporting the OpenStudio Model, but it is not editable in the same way as the EnergyPlus IDD, because information in the OpenStudio IDD is compiled into the C++ source code. That said the limits mentioned in this topic should not apply to the OpenStudio Model. It would not be until you actually try to run a simulation with EnergyPlus that these limits would come into play.

Kyle Benne's avatar Kyle Benne  ( 2015-05-05 15:18:25 -0500 )edit

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Asked: 2015-05-05 14:17:52 -0500

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Last updated: May 05 '15