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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'>Alvaro,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'>I can only speak to the EnergyPlus side of things (not
LEED). You will have to look into the created .idf and analyze the individual
cases through customized outputs to verify the system is working as you desire.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'>From the one error you listed in your post, the data center
cooling coil is working to heat the air stream on January 1st at 4 in the
morning. The air entering the coil is 54F (12.17C) and the setpoint is 52.5F
(11.41C). The temperature of the water entering the coil is 54F. The problem
here is that 54F water can’t cool the air to 52.5F, but since ‘cooling’ is
required, E+ doesn’t know how to react. With the reported chilled water
temperature, the chiller is likely not on. (I’ve seen that error a time or two,
and generally the chiller wasn’t on and there was no flow in the chilled water loop,
so the model was not particularly compromised.) You’ll want to verify how the
system is reacting at that timestep and the one after to make sure there isn’t
a deeper issue.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'>I don’t think the supply fan pressure would be directly
causing the issue, possibly just adding enough heat to require cooling at more
timesteps. I would check how the Setpoint Managers were set up in the .idf
input file, which may likely be the root cause.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'>I suggest using the Output:Variable objects to verify
accurate system performance at the timesteps in question, such as the ones
listed below. You may also want to output some air temperatures across the air
handling unit and their corresponding setpoints.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'>Output:Variable,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'> *, !- Key Value<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'> Chiller Evap Water Outlet Temp , !- Variable Name<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'> Timestep; !- Reporting Frequency<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'>Output:Variable,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'> *, !- Key Value<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'> Chiller Evap Water Mass Flow Rate , !- Variable Name<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'> Timestep; !- Reporting Frequency<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'>Output:Variable,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'> *, !- Key Value<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'> Chiller Evap Heat Trans Rate , !- Variable Name<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'> Timestep; !- Reporting Frequency<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'>Output:Variable,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'> *, !- Key Value<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'> Total Water Cooling Coil Rate , !- Variable Name<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'> Timestep; !- Reporting Frequency<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'>Output:Variable,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'> Cooling Coil Inlet, !- Key Value<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'> System Node MassFlowRate , !- Variable Name<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'> Timestep; !- Reporting Frequency<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'>If you still have questions about the .idf file, you can
contact the EnergyPlus Help Desk. <http://energyplus.helpserve.com/><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<div>
<p class=MsoNormal><strong><b><font size=2 color=navy face=Arial><span
style='font-size:10.0pt;font-family:Arial;color:navy'>Elyse Malherek</span></font></b></strong><font
color=navy><span style='color:navy'><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Applications Engineer</span></font><font
color=navy><span style='color:navy'><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>McQuay International</span></font><font
color=navy><span style='color:navy'><o:p></o:p></span></font></p>
<p class=MsoNormal><em><i><font size=2 color=navy face=Arial><span
style='font-size:10.0pt;font-family:Arial;color:navy'>a member of DAIKIN group</span></font></i></em><font
color=navy><span style='color:navy'><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>763.553.5379 (Office)</span></font><font
color=navy><span style='color:navy'><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><a href="mailto:elyse.malherek@mcquay.com"><font
size=3 face="Times New Roman"><span style='font-size:12.0pt;font-family:"Times New Roman"'>elyse.malherek@mcquay.com</span></font></a></span></font><o:p></o:p></p>
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<p class=MsoNormal><b><font size=2 face=Tahoma><span style='font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>From:</span></font></b><font size=2
face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'> bldg-sim-bounces@lists.onebuilding.org
[mailto:bldg-sim-bounces@lists.onebuilding.org] <b><span style='font-weight:
bold'>On Behalf Of </span></b>Alvaro Urrutia<br>
<b><span style='font-weight:bold'>Sent:</span></b> Monday, October 17, 2011
1:08 PM<br>
<b><span style='font-weight:bold'>To:</span></b> Bldg-sim@lists.onebuilding.org<br>
<b><span style='font-weight:bold'>Subject:</span></b> [Bldg-sim] Severe errors
for Fan Power modelling of VAV system in Energyplus</span></font><o:p></o:p></p>
</div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
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<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>Dear all:<o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'> <o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>In a baseline
building modeling for LEED EApr2 documentation, I have some troubles with the
simulation reports that shows unusually high amounts of severe errors
(over 1000); when I try to model System Fan Power according G3.1.2.9. and
procedure proposed by James V Dirkes II, PE in a previous post (pro-rating fan
power to supply/ret</span></font><font face="MS Mincho"><span style='font-family:
"MS Mincho"'></span></font>urn fans per 90.1-2007?).<o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'> <o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>I am concerned if
we can be observed by LEED reviewer team about this severe warnings.<o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'> <o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>Simulation
details:<o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'> <o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>-Baseline model
consist of six-levels building for typical office usage (8000m2 area approx.)<o:p></o:p></span></font></p>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>-HVAC system type
8, VAV with PFP zones according ASHRAE 90.1-2007 appendix G.<o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>-Energyplus
6.0.0.023 software has been used.<o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>-HVAC systems has
been modeled with HVAC templates in this configuration:<o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>
-Chilled Water loop with HVACTemplate:Plant:ChilledWaterLoop, Chiller and <st1:place
w:st="on"><st1:PlaceName w:st="on">Cooling</st1:PlaceName> <st1:PlaceType
w:st="on">Tower</st1:PlaceType></st1:place><o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>
-System-side equipment with HVACTemplate:System:VAV<o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>
-Zone-side equipment with HVACTemplate:Zone:VAV:FanPowered<o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'> <o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>-System Fan
Power modeling details:<o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>
-Supply Fan Total Efficiency = 0.6 <o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>
-Supply Fan Delta Pressure = 1495 Pa<o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>
-Supply Fan Motor Efficiency = 0.9<o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'> <o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'> <o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>-Severe errors
details:<o:p></o:p></span></font></p>
</div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>
-When Supply Fan Delta Pressure exceeds 500Pa, simulation error
log exposes unusually high amounts of recurrent severe errors like that
(over 1000 severe errors):<o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'> <o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 color="#666666" face="Courier New"><span style='font-size:12.0pt;
font-family:"Courier New";color:#666666'> ** Severe **
FindRootSimpleController: Controller error for controller =
SYSTEMVAV_DATACENTER COOLING COIL CONTROLLER<br>
** ~~~ ** Environment=<st1:City
w:st="on"><st1:place w:st="on">SANTIAGO</st1:place></st1:City>, at Simulation
time=01/01 04:30 - 04:35<br>
** ~~~ ** Controller function
is inconsistent with user specified controller action = Reverse action<br>
** ~~~ ** Actuator will be set
to maximum action<br>
** ~~~ ** Controller control
type=Temperature<br>
** ~~~ ** Controller temperature set point
= 11.41 [C]<br>
** ~~~ ** Controller sensed temperature =
12.17 [C]<br>
** ~~~ ** Controller actuator mass flow
rate set to 0.70 [kg/s]<br>
** ~~~ ** Controller actuator temperature
= 12.20 [C]<br>
** ~~~ ** Note: Chilled water
coils should be reverse action and the entering chilled<br>
** ~~~
** water temperature
(controller actuator temperature) should be below the setpoint temperature<br>
** ~~~ ** Note: Hot water
coils should be normal action and the entering hot<br>
** ~~~
** water temperature
(controller actuator temperature) should be above the setpoint temperature</span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>
-Also I tried to reduce Supply Fan Total Efficiency and maintain Supply Fan
Delta Pressure less than 500Pa but severe errors also occurred.<o:p></o:p></span></font></p>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> <o:p></o:p></span></font></p>
</div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>Suggestions to
reduce this errors or modeling system fan power in a different way?
<o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>Any comments will
be appreciated....<o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>Regards<o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'> <o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'> <o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>Alvaro Urrutia
Astorga<o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>Arquitecto.<o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'> <o:p></o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'> <o:p></o:p></span></font></p>
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