Location for applying HVAC components (HB-Energy)

[DreamADreammmm2023]

Hi all,

I have one confusion related to HVAC components under HB-E.
I’d checked many posts in the past but most of them are using HVAC components under HB-legacy.

I tried applying HVAC directly after constructing the geometry (adjacency), as shown in the picture below, but an error appeared and no graphic results were shown.

Then I changed the location (and components) to apply the HVAC to the room, and results are shown this time.

I’m not sure if there should be a correct location for applying the HVAC components? As I’ve not yet figured out how the HB system is working in grasshopper.
Is any of these ways of applying HVAC correct?

The GH file is attahced for your reference.
HB energy for model2 0425.gh (862.2 KB)

Thank you in advance for your help!

[JimMarsh]

I believe you need to add HVAC to the Room object. (At least that’s what I’m doing now and it’s working.)
I think of the Room as the finished baseline object and things like Program, Constructions, HVAC, etc as modifiers to that baseline Room.

[chris]

Thanks for trying to answer the question, @JimMarsh , and you’re right that is the correct way to assign HVAC systems but I think @DreamADreammmm2023 is asking specifically why the HB Thermal Load Balance is not working when a detailed HVAC template is assigned.

@DreamADreammmm2023 , this should give you the answer to your question:

Honeybee_Energy Balance data matching error for model

Yes, @AbrahamYezioro has correctly identified the use of (non ideal air) detailed HVAC as the source of the error. But it’s not a bug and let me explain why you aren’t able to construct energy balances or match data to rooms with detailed HVAC results. When you run a simulation with detailed HVAC, the energy use happens on the basis of each piece of HVAC equipment rather than each room like ideal air systems. So I can have one boiler that serves 10 rooms and I can get the fuel energy use of th…

In short, you need to use ideal air systems if you want to use the thermal load balance component.

[DreamADreammmm2023]

Thanks Chris for the answer. I understood the working principle behind now.

One more question I’d like check with you here (hopefully not a stupid one).
By applying ideal air HVAC, can I still apply a customized ventilation schedule in the system? Or does the ideal air HVAC system already have a default ventilation schedule?

Thanks in advance for your help!

[chris]

Hi @DreamADreammmm2023 ,

Mechanical ventilation requirements and schedules are specified separately from the HVAC system. In particular, you can assign a ventilation schedule using the HB Apply Room Schedules component.

As long as the HVAC system that you have selected can deliver ventilation air, then the minimum ventilation requirement and the ventilation schedule will be met by the HVAC system. And, yes, the Ideal Air System can deliver ventilation air. The only HVAC systems that cannot deliver ventilation air are the ones you apply with the HB HeatCool HVAC component.