Sizing for cooling and heating not works

Hi Community!

I have set the sizing factor for cooling and heating as 1.0 with HB sizing parameter component as below.

But it was not changed in simulation, the idf and result report show the simulation still used the default value for sizing.

May I know how to fix this issue?
Thank you!

Best regards

Hi @gogog ,

I can’t recreate the case described in your screenshots. I set the sizing factors to 1:

… and they show up correclty in the IDF:

Are you sure that you’re looking at the correct IDF?

Or do you have a minimal sample file that recreates your case here?

Hi @chris
Thanks for your feedback.
I think I found the problem, if I connect vintages data to eff_standard input, then no matter what sizing factor I set, the simulation will be using default value.
If there is no input for eff_standard, then sizing factor works.
Is it necessary to set the efficiency standard in sizing component?
This input seems has great impact on the final results.

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Ah, this is good to know:

In this case, then it seems OpenStudio Standards is overwriting the sizing factors in order to apply the efficiency standard according to ASHRAE 90.1. The ASHRAE 90.1 standard states that factors of 1.15 and 1.25 should be used. So the efficiencies would not be applied correctly if the factors were not overwritten.

Maybe I can add a warning to the component so that others don’t get surprised by this. I’ll try to do this tomorrow.

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Oh, I see, so the efficiency standard here is not only for system efficiency, it will also touch the system capacity.
Thanks for your clarification, Chris!

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FYI, I added a new warning to the component:

Now, people will get a message about this if they set both the efficiency standard and one or both factors:

This should hopefully prevent potential confusion in the future.

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