eQuest Activating the Packaged Desiccant Option

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Does anybody know how to activate the Packaged Desiccant option in eQuest? I have created some curves that I think might work and they show up as part of the possible selectable curves when I click on the Packaged Desiccant Tab curves individually, but I can't get the Design Wizard to select this curve or indeed, any curve from the possible list that appears. What am I missing? Some other part of another tab that needs to be activated? If so, where? I just assumed that this option worked and if I could make curves, I could use it. Maybe it doesn't work? If this is true, I am going to be peeved.

Thanks for listening.

Kathryn Kerns's picture
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Joined: 2011-09-30
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More things unpackage themselves in the Detailed Edit Mode.

Go there and see if your wishes come true....so you don't get peeved...

John R. Aulbach, PE, CEM

John Aulbach's picture
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Joined: 2011-09-30
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I could not enable the packaged desiccant curves but setting the
"maximum humidity" value on the basics tab of the system enables the
Desiccant Performance Curves and you can set your add on desiccant type
to Solid Vent Air 1 and select the appropriate control
mode/configuration to (hopefully) give you the closest system.

Good luck!

bfountain's picture
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Joined: 2011-09-30
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I am sorry, I forgot to mention I started in the Design Wizard and then went to Detailed Edit mode, which is where I discovered I couldn't activate the Packaged Desiccant curves.

Kathryn Kerns's picture
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I can do that, and indeed I activated the the liquid heat pump option to get some idea what kind of dew point I was looking for. But that is not really what I want and the solid desiccant doesn't option doesn't have curves you can adjust (at least none that I could find). So you can't get the Packaged Desiccant to work either? Anyone else have success?

Kathryn Kerns's picture
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I'm not quite sure what you are getting at or want to do. Speculating I
would assume you are working with outside air and heat recovery. If
that is the case, in the DD wizard, under the air side HVAC tab right
click on your system, select properties. Go to outdoor air, heat
recovery 1, ERV device installed, select yes, in the pop-up select
enthalpy wheel. You can also select stand alone in one of the tabs as
well. There are various performance items you can specify, and I would
assume Equest would then allow you to select a performance curve as well.
Bruce Easterbrook P.Eng.

Bruce Easterbrook's picture
Joined: 2011-09-30
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Bruce, I am trying to enable the Packaged Desiccant option in Detailed
Edit. The system I want to model is a packaged unit to be added to a
DOAS. This unit contains proprietary desiccant wheels and heaters. It
has performance curves. I wish to make performance curves and activate
them in the Detailed Edit mode Packaged Desiccant tab. The curves that I
made show up as selectable in the Packaged Desiccant tab, along with
other curves, but I can't get any of these curves to appear as a
selected in the Packaged Desiccant tab. I can't get any of the curves
selections that show up in the drop down menus on this tab to select,
either. I also can't access the library or create selection that shows
up in the drop down menu.

So my question is, what do I need to do to get the Packaged Desiccant
tab to work?

Kathryn Kerns

Kathryn Kerns's picture
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Kathryn,

I believe if you read the documentation, the solid desiccant model is "hard
wired" - no curves are available.

The only work-around I know of is to model it as a liquid desiccant system
and enter the curves that are appropriate for the solid desiccant system.

Mike

Michael Andelman's picture
Joined: 2011-09-30
Reputation: 0

The DOAS will be the system you need to add the ERV to. I normally
do this in the DD wizard and that was what the previous instructions
were for. Take a copy and go back to the DD wizard, it will warn you
that you are going to lose information you have added in the detailed
edit and you will. Go back anyway, you have a copy to use later in the
detailed edit. Follow my instructions to turn on the ERV, you may or
may not want to set it up as stand alone, that will depend on how you
are modelling your system. Once you have the enthalpy wheel turned on
you should be able to select your custom curve and replace the default
one Equest is using. Run your simulation and then compare your run in
the wizard to your detailed edit file. Before you start adjusting the
detailed edit file make another copy. You should be able to look at
your summary sheets on the 2 runs and determine which settings are
different and adjust the detailed edit so it is similar the the output
of the DD wizard. I have never done it this way but I think once you
create a template in the DD wizard to refer to you should be able to
spot the differences in the detailed edit and make changes to get you
back on track. You might also steal portions of the INP file from the
DD wizard and place them in the detailed edit. If you don't have too
much information in the detailed edit added you could just restart with
the DD wizard. Make sure you use copies so you don't lose what you
have. Also note a DOAS can be tricky in Equest. Make sure your
difficulties are not due to how you have modelled it. Good luck.
Just as a general observation, don't get into the detailed edit too
quickly. The DD wizard should handle 95% of all situations, if you
can't get it to run in the DD wizard going into the detailed edit will
just magnify your problems. I stay here and continually go back into
the DD wizard to tune my model. If you don't add anything in the
detailed edit you have nothing to lose. To do this go to the project &
site tab, go to the top and select mode, select wizard data edit. Using
this method I incrementally build my model, making sure each addition
runs. It makes it easier to find errors because you add to the model in
sections. If it doesn't run you have a smaller number of variables to
work on to get it running. I just use the detailed edit to modify
control points etc to fine tune everything but that can also be done by
going back into the wizard.
Bruce Easterbrook P.Eng.

Bruce Easterbrook's picture
Joined: 2011-09-30
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Thanks Mike, I am beginning to believe you are right. I am trying a
couple of other sources, but I may just have to modify the liquid heat
pump curves to suit my purposes. It does seem strange that the Packaged
Desiccant tab is available but nonfunctional, however. I would have
thought that if someone had gone to the trouble of creating the tab,
they would have activated it. Oh well.

Kathryn Kerns

Kathryn Kerns's picture
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Joined: 2011-09-30
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Bruce, the heat wheel shown in the eQuest Outdoor Air Heat Recovery tabs
is only part of the packaged desiccant unit. As far as I know, the
eQuest Outdoor Air Heat Recovery tabs 1 and 2 have no performance curves
associated with them. If there are performance curves associated with
the heat wheel shown in these tabs, please e-mail me their names. The
packaged desiccant unit I am trying to model has a proprietary heat
wheel and exhaust heaters that dry out the incoming air more effectively
than a regular heat wheel. This is why I wanted to use the eQuest
Packaged Desiccant tab. I am beginning to believe that this tab is not
functional and so I will probably have to modify the Add On Desiccant
tab liquid heat pump curves if I am going to get anywhere. Thanks for
trying.

Kathryn Kerns

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