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

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.


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Patrick O&amp;#039;Donnell's picture
Joined: 2011-09-30
Reputation: 0

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


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

Johnson, Anne's picture
Joined: 2011-09-30
Reputation: 0


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


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

Bishop, Bill2's picture
Joined: 2011-09-30
Reputation: 0

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

John Aulbach's picture
Joined: 2011-09-30
Reputation: 1