A fully customized hvac system (VAV Reheat)


Hi All,

Just finished the first test of full VAV Reheat hvac system (sort of). This is a new workflow for whom want to build your own hvac system in grasshopper with the current honeybee energy workflows.

Stay tuned, and please let me know if you have any wishes.


Ironbug Beta Release
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@MingboPeng, Well done! I think if you make a short tutorial and show how it all goes together it will be most likely that others will share their thoughts and wishes with you.


@MingboPeng This workflow is awesome.Please tell me when is available to download these components. And I have a question, ASHRAE 90.1 require each HVAC system .per floor. If we want to create multiple HVAC system, How to make it true easily?

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@mostapha Yes, sure. will do.


@minggangyin, in honeybee, you can use separate zones by floors and remove flatten on “HVAC system”. This will create systems by floors for the most cases.

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If you pass a DataTree, zones in each branch will be considered as a separate floor.

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Excellent work, @MingboPeng ! What systems are you thinking of adding after VAV? It looks like you have many of the HVAC components to build the other baseline systems.


Hi @chris, I have some more HVAC components included in the library, but not exposed in GH yet. Building the systems is for testing each component to see if they can really go together. The next system I will test probably is VRF system, and some zone-based systems. Definitely there is a long way to go.

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I’m attempting to replicate this methodology for modeling an Active Chilled Beam + DOAS system in Ironbug…but that resulted in a few component errors.

the Chilled Beam component error is: 1. Solution exception:Sequence contains no elements
the Condenser Water demand branches component error is: 1. Solution exception:Object reference not set to an instance of an object.

Note: The AirTerminal component doesn’t produce errors when I model the VAV w/ reheat setup.
Note: The Condenser Water demand branch produces an error because the “ToCondenser” on the chiller is “NULL”. What settings need to be added to parameters to enable the condenser??
any insight?

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Hi @josh.greenfield
Thanks so much for your testing.
You helped find some bugs that mainly was because I didn’t check those three components carefully.
Here is a fixed version.Ironbug_20181028.zip (170.1 KB)
Please download this zip file, and copy two updated files to C:\Ironbug folder, and override the old files.

Thanks ,

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Ironbug Beta Release

thanks for updating the components…I really appreciate it!

note: the .zip file needs to be UNBLOCKED before the files are extracted and copied into the C:\Ironbug folder.

Ironbug Results Testing