Where to find summary of overridden defaults etc.

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Hi,

I know that when a run has issues, it creates an ATTN report with the warnings listed. But how can I find out how many default values have been overridden without going through every screen and counting them?

Thanks, all!

MARK DARRALL, AIA, LEED AP BD+C, NCARB

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Hi Mark,

For eQuest, I don't believe there is any reasonable way to tally
"default overrides." For LEED submittals, I typically enter zeroes at
the corresponding template queries, and that's what I've suggested to
others for initial submittals. I've heard others enter "9999" in all
fields without comment, but 0 seems less conspicuous to me =).

There's further discussion on this topic in the archives -
bookmark/favorite these links if you haven't already:

http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/

http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/

If a reviewer were to push me to come up with a figure without any
specific guidance after an initial submittal, I suppose I would paste
the .inp file into a word document, ctrl+f for instances of the text
".." without quotes, and explain that number represents an estimate of
the number of non-library entries in the project (screengrab):

I would probably wonder about the reviewer somewhere along the way
too... Anyone familiar with eQuest and LEED knows there's no way to
finish a 90.1-based model without a horde of non-default entries... I'm
having difficulty guessing at how this figure could help an eQuest model
reviewer do their job properly. Perhaps it's specific to other software
packages... Thoughts anyone?

To be clear, I'd sooner advise just entering 0's in lieu of jumping
through any unnecessary hoops.

~Nick

NICK CATON, E.I.T.

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If in the baseline (and may be the proposed case), I have made changes from
the auto-sizing (and from the proposed design) to reduce the unmet hours, I
count that as default over-ridden. This is usually a small number (less than
5 if I remember correctly).

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R B
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The DOE2.1E Manual ?DOE-2 BDL SUMMARY, Version 2.1E? lists all the commands and keywords with the Default and Minimum-Maximum range. The DOE2.1E Manual ?DOE-2 Supplement, Version 2.1E? has BDL Examples for modeling Loads, Systems and Plant. This information is not available in the DOE22 manuals.
It used to be possible to download the DOE2.1E manuals from the LBNL website http://gundog.lbl.gov/ The LBNL website now shows http://esl.tamu.edu/pub/DOE-2_OCR_Manuals/ for searchable DOE21.1E documentation which won?t open.
Here is a useful website on energy use by building type http://buildingsdatabook.eren.doe.gov/

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Thanks, everyone!

Don't forget, too, that the Appendix G requirements don't always jive with default eQ values. Also, my reviewer has asked that autosizing not be done for baseline, which probably meant more overrides...

I appreciate the tip on searching the .inp file. Thanks!

MARK DARRALL, AIA, LEED AP BD+C, NCARB

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Just a couple of comments, Mark. If a default was overridden, it would be
you who did it so you would know what you overrode it with. If I am
misunderstanding and you just couldn't see what the default was you can view
it, usually by right clicking on the input box.

I am curious why the reviewer asked that autosizing not be done for the
baseline. I was reading my Std 90 2004 User's guide this morning and was
kind of surprised that in it they more or less suggest you need to oversize
by hand. I'm not sure why. I know that you need to be careful where you put
the 15% and 25% sizing increases in eQUEST but it's relatively easy to get
them in the right spot.

As a check let me know what you think of my methodology. I set the system
sizing ratio on the first screen of the Air-Side HVAC System to 1.0, and
then set the Cool Size Ratio to 1.15 on the first screen under the Cooling
tab, and the Heat Size Ratio to 1.25 of the first screen under the Heating
tab. Is this what others do?

Carol

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In brief, I do what Carol's describing. I haven't read up on what the
user's manual might say about "manual oversizing," but all my baseline
system capacities are auto-sized using the same heating/cooling capacity
factors described... I've yet to encounter any opposition from my
reviewers using this approach.

For clarification and in contrast: baseline system efficiencies and fan
energies are not auto-sized, but rather separately calculated and
entered by hand, working from the auto-sized heating/cooling/airflow
capacities derived from a sizing run.

If after a sizing run, incrementally adjusting heating/cooling
capacities were necessary to correct unmet hours (though I haven't run
into that case for a long while - when it comes up it's usually resolved
checking/fixing other items), I suppose I would intuitively adjust the
1.15/1.25 factors a bit at a time until the numbers worked out, then
proceed with the efficiency & fan calcs.

As to a "manual" capacity oversizing approach: It's news to me...

~Nick

NICK CATON, E.I.T.

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You're probably getting at the nature of the reviewer's comment better than
I did, Nick. I read "over-sizing" rather that "auto-sizing" because I had
just read that section in the User's Manual.

So basically we are doing auto-sizing but we call it "sizing runs" which we
use to input the pertinent data into the baseline, e.g. kW/cfm, cooling coil
size, heating coil size and/or cfm, or some combination of output from our
sizing runs.

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Thanks for the feedback, everyone.

Overridden defaults always appear as red inputs, so identifying them isn't the issue - it's the time involved in going through the entire set of input boxes to find them all!

What I did for App. G baseline sizing was left the heating and cooling capacities blank and ran the sim. I then viewed the calculated capacities in the system summaries, adjusted them per the App. G oversizing factors, and plugged those numbers back into the coil size input box. For some reason, the coil sizing factor input box wasn't available, or I would have just put the factors in there.

Thankfully I have no unmet hours, though I do have some hours out of throttling range. I may try to track that down, though there seems to be no LEED or App. G requirements for that.

What I'm trying to do here is get by the reviewers, so as much as I can, I'll give them what they've asked for. These models are already significantly different from what they originally reviewed (the originals did not include a very large hood and makeup air unit that alone uses more energy than the other 7 AHUs combined).

Thanks again,

MARK DARRALL, AIA, LEED AP BD+C, NCARB

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Mark,

For terminology, in eQuest, "hours outside of throttling range" = "unmet
load hours".

Jeremy R. Poling, PE, LEED AP+BDC

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