3.64 LEED Compliance Analysis - running notes/questions

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This question is specific to the new (3.64) LEED compliance analysis
within eQuest for generating baselines models:

Is there any means of bypassing assigning sub-occupancies to each space?
If, as a matter of course in developing the proposed model and
determining it's overall LPD, we should already have taken off all areas
and come up with a baseline LPD, may we ignore this assignment and
override with a calculated result? That's my situation and I'd like to
avoid re-taking off all the areas within my established zones if
possible...

NICK CATON, E.I.T.

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A quick heads up to anyone who hasn't tried this feature out yet:

If you have the choice, I'd advise anyone trying this out for the first
time to use a wizard-generated project created using eQuest 3.64. Make
a point to utilize those zone occupancy allocation screens while you're
at it. I'm cutting my teeth with this analysis tool on a finished
proposed model from 3.63, and it appears I am as such not able to take
advantage of some time-saving automation where it pulls that information
across from the wizards.

This is no fault of anyone else's by the way - the provided guide is
very helpful and useful... I'm just the sort of personality that decides
to build a furniture kit without referencing the instructions carefully
and later wonders what those leftover bits are for after the fact... =)

NICK CATON, E.I.T.

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Joined: 2011-09-30
Reputation: 605

After carefully following the provided guidelines for the new (v3.64)
LEED Compliance Analysis on a proposed model from 3.63, I clicked the
"Perform Compliance Analysis" toolbar button, and observed a bunch of
number crunching before seeing the following two popups:

The latter "Rules Evaluation Error List" dialog lists the same error
line exactly 28 times:

"Error - Assign zone to baseline floor system: CRule::Eval() error
posting symbolic (value 2.67146e-297) result to BDL"

For those who haven't been keeping score, James Geers recently observed
this same error appears to correlate with plenums and/or unconditioned
spaces. With that in mind, I spent the better part of yesterday trying
to replicate his proposed workaround to change plenums to 'conditioned.'
Specifically, you have to change the zone type at the zonal level (under
the Airside HVAC tab - not using the old/new space-level input fields).

I noticed something interesting though: The project I'm working on has
35 unconditioned zones (plenums and below-ceiling spaces). It has
exactly 28 unconditioned zones (plenum and otherwise) in single shell
(of 4). This is the only shell with a flr-to-clg not equal to its
flr-to-flr value. Some zones have a Z=0 (like mechanical rooms), so I
don't think it specifically has anything to do with the spaces
themselves being plenums so much as being part of a shell with
wizard-generated plenums.

Switching these unconditioned zones to conditioned at the zonal level
remedies the problem with the LEED analysis tool and permits a baseline
model to be generated (to the extent the current version allows). After
finishing the baseline generation one can go back and switch such zones
to be unconditioned again in both models if desired.

One more thing: The guide delineates a number of things it does not yet
do to create a finished baseline model - something not mentioned is
setting the "shading surface" property to "No" for exterior surfaces.

NICK CATON, E.I.T.

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Joined: 2011-09-30
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