Hi, everyone:
I have a question about the system type of APPENDIX G3.1.1.
As the below requirement. Is that means for an office building with a
garage, the garage system in the baseline building can be the same
system type with the purposed building . if not, what's the list for the
additional system?
Any suggestion should be appreciated .
Exceptions:
a. Use additional system type(s) for nonpredominant
conditions (i.e., residential/nonresidential or heating
source) if those conditions apply to more than
20,000 ft2 of conditioned floor area.
Thank you
Joey
Is the garage with air conditioning system? I mean heating and cooling. If the garage is just with mechanical ventilation, you should model it as design in the baseline model. If the garage is with air conditioning system(and the heating source is also same), however it still in an office building, I think the baseline system type is the same as the office baseline.
The 3.1.1 is applied to only conditioning system.
Jie
Hi, Jie & everyone:
Thank you so much about your suggestion. You make it more clear.
Do you have any suggestion about the additional system referred below?
Exceptions:
a. Use additional system type(s) for nonpredominant
conditions (i.e., residential/nonresidential or heating
source) if those conditions apply to more than
20,000 ft2 of conditioned floor area.
And I heard that the consumption of the garage ventilation system power should be seems as the process load. So it should be the same between the purposed and baseline model, no matter if the garage with heating. Is that right?
Thanks again.
Joey
???: Jenny Zhang [mailto:jenny.zhang at arup.com]
????: 2012?3?13? 11:47
???: Jiao, Joey; Equest-users at lists.onebuilding.org
??: RE: ASHRAE 90.1 system type question
Is the garage with air conditioning system? I mean heating and cooling. If the garage is just with mechanical ventilation, you should model it as design in the baseline model. If the garage is with air conditioning system(and the heating source is also same), however it still in an office building, I think the baseline system type is the same as the office baseline.
The 3.1.1 is applied to only conditioning system.
Jie
Hi Joey, according to ASHRAE 90.1-2007 and before if the proposed system is ventilation with heat, the baseline system should be with cooling and selected by Table G3.1.1A. And the virtual cooling system should be created in proposed model (identical to system modeled in baseline).
You could see that it is not reasonable to assume virtual cooling system in both proposed model and baseline, since cooling demand is not in actual building performance. In the New ASHRAE 90.1-2010 the terms about this issue has been changed.
G3.1.1 Baseline HVAC system Type and Description
Exceptions:
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And in Type G3.1 Modeling requirements for Calculation Proposed and Baseline Building Performance
[cid:image005.png at 01CD0367.454F6B80]
If you are doing LEED modeling I think you could using the updated method.
best regards
Jie Zhang