Unable to assign a VAV "terminal type"

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I am working on a model for a project where multi-zone air handling systems are being converted to single-duct VAV systems. I have already completed the system changes so that all of the air handling units are single-duct VAV. However, I am unable to change the zones to include VAV boxes. Under each zone in the "Air Flow" tab, the "Zone Terminal and Fans" section is all grayed out and will not allow any changes. I tried deleting the zone and re-creating it, but I still have the same issue. Any advice is much appreciated!

Rob

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What are you calling your system type? It will have to be VAVS, PVAVS or
PVVT to be able to include VAV boxes.

Carol

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System Type is VAVS.

Thanks,

Rob

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Rob Young, PE

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I think the Zone Terminal and Fans line that is grayed out is only for PIU
systems, where boxes can be series, parallel and standard VAV. In VAVS, it
appears that they just default to standard VAVS. What kind of changes are
you trying to make?

Carol

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Rob:

Right-click on the gray area in VAV Terminal Type. Chose Edit/View User
Default, click User Defined Default Value and use the drop down arrow to choose
your VAV type.

To verify that the VAV terminal device is operating correctly, create a new
Thermal Zone Type Hourly Report Block for the VAV zone. It will verify that the
VAV box is varying the airflow.

Paul Diglio

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I have done this 50,000 in DOE-2.1E, but have forgotten the steps in eQuest.

I am trying schedule a boiler off for the months of April - October. I know
Load-Management is the key, but forgot how I am to set up schedules. This is not
the same as setting up the Flags in Economics.

A small example you may have would be appreciated.

John R. Aulbach, PE, CEM

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John,

You can change annual schedule for any schedule either it is flag or fraction or decimal (see attached screen shot)

-Ashu

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Hi John,

Wouldn't you just create a schedule with a bunch of weeks, e.g winter week,
summer week, winter week, where you had all the days as 0 for the summer?
You can use ON/OFF FLAG without a flag and it will just be on/off.

Carp;

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Thanks Paul, I did this and it worked!

Rob

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Rob Young, PE

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Hi Rob,
As Carol already replyed, the default for VAVS systems is a standard single duct VAV box. Making an entry of STD VAV under the greyed-out "terminal type" should not change your simulation results.

Hope that helps.

Kind Regards,

Molly Curtz

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Though that method does work to change what you see on the screen, it doesn’t do anything else. All zones under a VAVS system have standard VAV boxes, even if it is grayed out.

Matt Dubrovich, PE, CEM, BEMP

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