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[EnergyPlus_Support] Re: Cooling set-point not fully achieved



OK, then it goes like this (apparently, the catch was in sizing the 
water flows):
- basically, I increased these "a lot" and looked at the reported 
maximum flows
- the reported maximum flow, (with a large maximum design flow, which 
indeed solves the set-point problem) was, not 2, but about 4 times 
larger than the auto-size maximum water flow;
- which strikes me as odd, specially because the outside temperatures 
in the simulation period are between 7 and 10 ºC lower than the given 
design day;

In any case, the problem is located and solved. Thanks for the 
guidance.

An additional, unrelated question: if the pump if PUMP:CONSTANT 
SPEED, shouldn't the water flow graphics be "square-like"?

Regards,
Ana.

--- In EnergyPlus_Support@xxxxxxxxxxxxxxx, Richard Raustad 
<RRaustad@...> wrote:
>
> Then try again to manually size the coil in the problem zone to 
twice 
> the size reported in the eio file. Also increase the air flow rate 
for 
> that fan coil unit and fan to twice the autosized value. If htis is 
> happening in more than 1 zone, then just pick 1 for now to test 
this out.
> 
> Then tell me what happens to the maximum zone temperature. Did the 
> maximum zone temperature go down? Also tell me if the water flow 
rate is 
> at a maximum when the zone temperature exceeds the set point. You 
can 
> report "System Node VolFlowRate" for the coil water inlet node and 
fan 
> coil air inlet node to easily match volumetric flow rate with your 
inputs.
> 
> This just sounds like a sizing issue and should be easily resolved.
> 
> anarui.oliveira wrote:
> >
> > Apparently, yes, but I set it to autosize (and I think I already 
did
> > a trial with a larger, user-defined, water flow rate)...
> >
> > --- In EnergyPlus_Support@xxxxxxxxxxxxxxx 
> > <mailto:EnergyPlus_Support%40yahoogroups.com>, Richard Raustad
> > <RRaustad@> wrote:
> > >
> > > I have not looked at your input file, can you tell me if the 
water
> > mass
> > > flow rate through the fan coil is at a maximum when the cooling 
set
> > > point is not met?
> > >
> > > anarui.oliveira wrote:
> > > >
> > > > Please forgive me for insisting, but I DO have some urgency on
> > this
> > > > one...
> > > > Again, thanks for any help,
> > > > Ana.
> > > >
> > > > --- In EnergyPlus_Support@xxxxxxxxxxxxxxx 
> > <mailto:EnergyPlus_Support%40yahoogroups.com>
> > > > <mailto:EnergyPlus_Support%
40yahoogroups.com>, "anarui.oliveira"
> > > > <anarui.oliveira@> wrote:
> > > > >
> > > > > Hi again.
> > > > >
> > > > > I'm uploading a new file (Zone36598_cFancoil_exp), hoping 
that
> > > > someone
> > > > > can help me figure out why the cooling setpoints are not 
being
> > > > achieved
> > > > > for all times when the controls are active (namely in Zone
> > 36598).
> > > > The
> > > > > model consists of Fancoil units created with Compact HVAC, 
and
> > then
> > > > > edited in the expanded file.
> > > > > I tried several user-defined and sizing options, but 
couldn't
> > solve
> > > > the
> > > > > temperature peaks above 25ºC.
> > > > >
> > > > > Thanks in advance,
> > > > > Ana Rui.
> > > > >
> > > >
> > > >
> > >
> > > --
> > > Richard A. Raustad
> > > Senior Research Engineer
> > > Florida Solar Energy Center
> > > University of Central Florida
> > > 1679 Clearlake Road
> > > Cocoa, FL 32922-5703
> > > Phone: (321) 638-1454
> > > Fax: (321) 638-1439 or 1010
> > > Visit our web site at: http://www.fsec.ucf.edu 
<http://www.fsec.ucf.edu>
> > >
> > > UCF - From Promise to Prominence: Celebrating 40 Years
> > >
> >
> >  
> 
> -- 
> Richard A. Raustad
> Senior Research Engineer
> Florida Solar Energy Center
> University of Central Florida
> 1679 Clearlake Road
> Cocoa, FL  32922-5703
> Phone:   (321) 638-1454
> Fax:     (321) 638-1439 or 1010
> Visit our web site at: http://www.fsec.ucf.edu
> 
> UCF - From Promise to Prominence: Celebrating 40 Years
>




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