Cooling EIR and Supply Fan Energy broken down for PVAV w/ PFP (System 6)

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Dear eQuest folks,

The following comment turned up twice in the preliminary and final design
phase review.

*The SV-A reports indicates that the cooling efficiencies for the HVAC
systems were not correctly reflected in the Baseline model and the supply
fan energy has not been broken out as required. The response narrative to
the Preliminary Review comment number 1 indicates that the cooling
efficiencies were recalculated and then entered in the Wizard; however as
stated in the Preliminary Review, eQUEST performs this step automatically
between the wizard and detailed interface (for example, a 10.0 EER packaged
DX unit with efficiencies entered in the wizard is shown in the detailed
interface with a cooling-only EIR of 0.2878 (EER = 11.86)) Section G3.1.2.1
requires that where efficiency ratings, such as EER and COP, include fan
energy, the descriptor shall be broken down into its components so that
supply fan energy can be modeled separately. Note that the cooling
efficiency without the fan power is typically rated higher than when the
fan power is included as a component in the rated efficiency If appealing
this prerequisite, revise the Baseline model so that fans have been broken
out separately from the cooling EIR indicates in the SV-A report. *
*
*
I attach the sample SV-A and SV-B report below. I modeled this type 6
baseline system using a PIU, which, based on my digging in the archived
mailing list, is the closest way to model a VAV system with PFP boxes. The
cooling EIR was automatically generated in eQuest assuming the supply fan
energy (ARI 340/360) was subtracted from EER 10. Actually, in the previous
comment response, I calculated cooling EIR using two approaches found in
the archived mails (ARI and non-ARI conditions). But our reviews tended to
neglect the narratives and focus on how to confirm the supply fan energy
has been broken out per G3.1.2.1, although the SV-B report already showed
the modeled PFan.
*
*
*[image: Inline image 1][image: Inline image 2]
*
Any ideas on what additional proof documents I need to provide to meet the
reviewer's requirements?

Thanks
--
*? ?
Ting Wang 

Ting Wang
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