High Cooling and Fan energy use VAV? Advice needed

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Hi all,
I am having a hard time getting this VAV system to be efficient; more
specifically the cooling and fan energy seems way too high and I cannot
figure out why. This system serves a space in an insulated built-out
office space that is located within an insulated production space. The
production space has heating only and generates some of its own internal
loads.

It is the office spaces that I am concerned with (set on their own
meters EM1 and FM1 ). There is some load diversity i.e. some rooms have
some significant equipment and occupant loads while others do not.
* Cooling capacity seems reasonable(this system is auto sizing),
supply cfm seems normal.
* The fans are running whenever the system is on.
* Looking at the hourly reports, I think the economizer is working
properly and modulating open for free cooling when OA temp is below the
set threshold.
* Unmet load hours for cooling are also very high.
* Internal loading, occupancy, etc should be accurate however it
should be noted that infiltration into the office spaces is
intentionally set pretty high accounting for minimal sealing of spaces.

I think I have some of the controls goofed up or scheduling conflicts
but am not sure. Thank you very much in advance for any
assistance/insight you can provide!! Attached are the modeling files.

-Patrick

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Patrick O&amp;#039;Donnell's picture
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Hello - I am new to EQUEST. I am trying to find the definition for some
of the terms on the Air-Side HVAC System Parameters page. The Item Help
is just a reference to Volume 2: Dictionary. Where can I find that
resource?

Thanks!

Anne Johnson, P.E., LEED(r) AP

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Anne,

With eQUEST open, look in "DOE-2 Help" under the Help menu. Select the
"Contents" tab or search for the term(s).

Regards,

William Bishop, EIT, BEMP, LEED(r) AP

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Quick take, as I haven't look at your runs. But setting the Thermostat to Reverse Action and having a throttling range of 4 - 6 DegF (Forget the R they have displayed). That should knock down your unmet hours, and maybe your fan.

John R. Aulbach, PE, CEM

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