Basic Question Regarding HVAC Zoning

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I only want to make sure I'm going about this in the correct manner.

The project I'm using to teach myself this program is a largish elementary school. I've made a few models with simplified zoning, and they worked alright. I wanted to graduate to custom zoning, with system types that might better reflect our typical design (Parallel VAV in classroom blocks, single zone VAV in cafeteria/gym, etc).

I traced my CAD file for the envelope and preliminary zoning plan, and set up a couple air-side systems (all in the DD wizard). I skipped over the "area allocation" dialog, because I discovered that the "zone groups" dialog allows you to override area allocations per zone group. So, I set up a classroom zone group, and added each classroom zone to it, an office zone group, etc... I changed the area allocation in the zone group dialog for each zone group to reflect the zone usage. At this point, does eQuest pretty much ignore entire building area allocation numbers in the formal "area allocation" dialog, because I have custom allocation profiles set up for each zone group? I did this because the unless I'm mistaken, eQuest only allows you to assign systems to zone groups, not individual zones. The model is coming up short, and this method of zone/system assignment just seems wrong to me. Am I doing this correctly?

Related question: does eQuest allow you to set up occupancy profiles for each zone, so that occupancy diversity (flow of children from classrooms to cafeteria, etc) can be modeled?

Thank you guys. Lurking the list for past couple weeks has been very informative. Have a good weekend.

Cole Hudson, E.I.T.

Cole Hudson's picture
Joined: 2011-09-30
Reputation: 0

Hi Cole,

Wizard-level system/zone assignments are not the most intuitive thing.
Whenever in doubt, the best thing to do is to try one option, then
finish the wizards and observe the results in detailed view (look to the
airside component tree).

Your method sounds good. The zone groups dialog does override the
percent-based allocations if you define something new (i.e. this group
of spaces under one system is 100% office).

Whether you wind up with one system serving a bank of 5 adjacent
offices, or 5 separate systems, or no new systems depends on the "system
per..." option for the system you select in the custom zone dialog
dropdown... ("unintuitive" is the kindest word I've come up with anyway
^_^)! Play around with that to achieve what you need. Note that a
typical VAV system should look like one "system" in the component tree
over all its child zones, with the individual terminal units defined at
the zone/space level.

eQuest can handle many unique profiles (the upper limit per project is
more than 1,000), so you could easily model the "flow" of children as
you describe. That said, the wizards will only generate one set of
schedules (occupancy and otherwise) per shell, and your control over
that output is limited - you are describing a "post-wizard" task right




Nick-Caton's picture
Joined: 2011-09-30
Reputation: 605