<html><head><style type="text/css"><!-- DIV {margin:0px;} --></style></head><body><div style="font-family:times new roman,new york,times,serif;font-size:10pt">Actually what everyone is calling dt is more accurately referred to as lift. It is the difference between the saturated evaporating temperature and the saturated condensing temperature, which is different than the condenser water temperature and the evaporator water temperature.<br><br>A more accurate curve can be built if you have the chiller manufacturer model both these variables for you, rather than leaving the evaporator water temperature constant and just varying the condenser water temperature. Any change in the evaporator pressure will effect the condensing pressure and any change in the condensing pressure will effect the evaporator pressure.<br><br><div style="font-family: times new roman,new york,times,serif; font-size: 10pt;">Paul<br><div style="font-family: times new
roman,new york,times,serif; font-size: 12pt;"><font face="Tahoma" size="2"><hr size="1"><b><span style="font-weight: bold;">From:</span></b> Nick Caton <ncaton@smithboucher.com><br><b><span style="font-weight: bold;">To:</span></b> James Waechter <jamesw@McKinstry.com>; equest-users@lists.onebuilding.org<br><b><span style="font-weight: bold;">Sent:</span></b> Fri, February 25, 2011 1:21:42 PM<br><b><span style="font-weight: bold;">Subject:</span></b> Re: [Equest-users] using IPLV in eQuest<br></font><br> <style> <!-- _filtered {font-family:"MS Mincho"; panose-1:2 2 6 9 4 2 5 8 3 4;} _filtered {font-family:"Cambria Math"; panose-1:2 4 5 3 5 4 6 3 2 4;} _filtered {font-family:Calibri; panose-1:2 15 5 2 2 2 4 3 2 4;} _filtered {font-family:Tahoma; panose-1:2 11 6 4 3 5 4 4 2 4;} _filtered {font-family:"Stylus BT"; panose-1:2 14 4 2 2 2 6 2 3 4;} _filtered { panose-1:2 2 6 9 4 2 5 8 3 4;} _filtered {font-family:Verdana;
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margin-right:0in; margin-bottom:0in; margin-left:.5in; margin-bottom:.0001pt; font-size:12.0pt; font-family:"serif";} span.EmailStyle17 { font-family:"sans-serif"; color:windowtext;} span.EmailStyle18 { font-family:"sans-serif"; color:#1F497D;} span.BalloonTextChar { font-family:"sans-serif";} span.Heading5Char { font-weight:bold;} span.BodyTextChar { } .MsoChpDefault { font-size:10.0pt;} _filtered { margin:1.0in 1.0in 1.0in 1.0in;} div.Section1 {} --> </style> <div class="Section1"> <p class="MsoNormal"><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(31, 73, 125);">James et al,</span></p> <p class="MsoNormal"><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(31, 73, 125);"> </span></p> <p class="MsoNormal"><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(31, 73, 125);">Rohini will need to create performance curves to make this particular
comparison. Otherwise using the default curves will result in identical part load performances.</span></p> <p class="MsoNormal"><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(31, 73, 125);"> </span></p> <p class="MsoNormal"><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(31, 73, 125);">The following is excerpted from the following (short) recommended reading concerning what IPLV<span> means: <a target="_blank" href="http://ashrae-cfl.org/2010/03/understanding-iplvnplv/">http://ashrae-cfl.org/2010/03/understanding-iplvnplv/</a></span></span></p> <p style="margin-left: 0.5in;">IPLV (or NPLV) = 0.01A+0.42B+0.45C+0.12D</p> <p style="margin-left: 0.5in;">Where:</p> <p style="margin-left: 0.5in;">A = COP or EER @ 100% Load</p> <p style="margin-left: 0.5in;">B = COP or EER @ 75% Load</p> <p style="margin-left: 0.5in;">C = COP or EER @ 50% Load</p> <p
style="margin-left: 0.5in;">D = COP or EER @ 25% Load</p> <p class="MsoNormal"><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(31, 73, 125);">John is saying knowing only the IPLV and the 100% load condition efficiency (variable ‘A,’ above) is not enough information to extrapolate the IPLV curves to compare the two chillers. </span></p> <p class="MsoNormal"><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(31, 73, 125);"> </span></p> <p class="MsoNormal"><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(31, 73, 125);">For the exercise of comparing the two non-centrifugal chillers of the same technology/type, I would just focus on making a custom EIR-FPLR (not EIR-fPLR&dT) for each chiller, and use the library CAP-FT AND EIR-FT curves. My understanding is the effects of temperature on capacity and EIR outside of centrifugal VSD chillers is
negligible. NOTE: Whenever using any of the default library chiller performance curves, that means you MUST normalize to and specify the chiller at ARI conditions – those curves aren’t normalized to anything else.</span></p> <p class="MsoNormal"><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(31, 73, 125);"> </span></p> <p class="MsoNormal"><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(31, 73, 125);">So! If you can find the IPLV A, B, C and D values for both chillers’ curves, you could come up with your EIR-FPLR curve coefficients (<u>curve type = quadratic or cubic</u>) using a curve-fit in excel… or alternatively make eQuest figure the coefficients by entering those points as raw data.</span></p> <p class="MsoNormal"><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(31, 73, 125);"> </span></p> <p
class="MsoNormal"><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(31, 73, 125);">You may more easily just make your own curves, following John’s advice and getting part load unloading curves (100%, 90%, 80%... etc) held at a constant chilled & condenser temperature to match the ARI* conditions (85CWT if this is water cooled) at which you’re specifying the chiller capacity/EIR. Again, you could either go into excel, normalize the data (review DOE2 help entry for EIR-FPLR), make a scatter chart, and get the coefficients using a curve fit… or enter the data as raw points into eQuest and the coefficients will be figured by eQuest… whatever makes more sense to you.</span></p> <p class="MsoNormal"><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(31, 73, 125);"> </span></p> <p class="MsoNormal"><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(31,
73, 125);">For others and personal future reference…. If you are looking to make an <u>EIR-fPLR&dT</u> curve (for centrifugal chillers or otherwise): Ask your rep instead for multiple (minimum 3) part load unloading runs, holding the delivered chilled water temp constant, and vary the condenser water temperature incrementally for each run (i.e. 85, 75, 65). Choose a range of CWT’s that cover the anticipated range to be encountered in the actual design. This will get you enough data to have the minimum 3 delta-T’s represented in your part load data points to build this curve correctly. You’ll be using eQuest “raw-data” entry method to make it generate the coefficients.</span></p> <p class="MsoNormal"><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(31, 73, 125);"> </span></p> <p class="MsoNormal"><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(31, 73,
125);">~Nick</span></p> <p class="MsoNormal"><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(31, 73, 125);"> </span></p> <p class="MsoNormal"><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(31, 73, 125);">* Rather than ARI conditions (85F CWT), you could be normalizing to Design condition EIR/CAP, provided you’re making a full set of custom curves in the same fashion.</span></p> <p class="MsoNormal"><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(31, 73, 125);"> </span></p> <div> <p class="MsoNormal"><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(31, 73, 125);"><img id="Picture_x0020_1" src="cid:1.3019653287@web83307.mail.sp1.yahoo.com" alt="cid:489575314@22072009-0ABB" border="0" width="119" height="37"></span><b><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(45, 77,
94);"></span></b></p> <p class="MsoNormal"><b><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(45, 77, 94);"> </span></b></p> <p class="MsoNormal"><b><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(45, 77, 94);">NICK CATON, E.I.T.</span></b><b><span style="font-family: "sans-serif"; color: rgb(45, 77, 94);"></span></b></p> <p class="MsoNormal"><span style="font-size: 7.5pt; font-family: "sans-serif"; color: rgb(204, 153, 0);">PROJECT ENGINEER</span></p> <p class="MsoNormal"><span style="font-size: 10pt; font-family: "sans-serif"; color: rgb(45, 77, 94);">Smith & Boucher Engineers</span><span style="font-size: 7.5pt; color: rgb(204, 153, 0);"></span></p> <p class="MsoNormal"><span style="font-size: 10pt; font-family: "sans-serif"; color: rgb(45, 77, 94);">25501 west valley parkway</span></p> <p class="MsoNormal"><span style="font-size:
10pt; font-family: "sans-serif"; color: rgb(45, 77, 94);">olathe ks 66061</span></p> <p class="MsoNormal"><span style="font-size: 10pt; font-family: "sans-serif"; color: rgb(45, 77, 94);">direct 913 344.0036</span></p> <p class="MsoNormal"><span style="font-size: 10pt; font-family: "sans-serif"; color: rgb(45, 77, 94);">fax 913 345.0617</span></p> <p class="MsoNormal"><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(31, 73, 125);"><a rel="nofollow" title="blocked::www.smithboucher.com"><span style="font-size: 10pt;">www.smithboucher.com</span></a></span><u><span style="font-size: 10pt; font-family: "sans-serif"; color: blue;"> </span></u><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(31, 73, 125);"></span></p> </div> <p class="MsoNormal"><span style="font-size: 11pt; font-family: "sans-serif"; color: rgb(31, 73, 125);">
</span></p> <div> <div style="border-width: 1pt medium medium; border-style: solid none none; border-color: rgb(181, 196, 223) -moz-use-text-color -moz-use-text-color; padding: 3pt 0in 0in;"> <p class="MsoNormal"><b><span style="font-size: 10pt; font-family: "sans-serif";">From:</span></b><span style="font-size: 10pt; font-family: "sans-serif";"> equest-users-bounces@lists.onebuilding.org [mailto:equest-users-bounces@lists.onebuilding.org] <b>On Behalf Of </b>James Waechter<br> <b>Sent:</b> Friday, February 25, 2011 10:55 AM<br> <b>To:</b> equest-users@lists.onebuilding.org<br> <b>Subject:</b> Re: [Equest-users] using IPLV in eQuest</span></p> </div> </div> <p class="MsoNormal"> </p> <p class="MsoNormal"><span style="font-size: 10pt; font-family: "sans-serif";">John,</span></p> <p class="MsoNormal"><span style="font-size: 10pt; font-family: "sans-serif";"> </span></p> <p
class="MsoNormal"><span style="font-size: 10pt; font-family: "sans-serif";">If the only parameter Rohini enters into the program is the full-load EIR – which he said is the same for both chillers – how will eQuest know to bend the curves differently for the two chiller options. It is my understanding that program would use the same chiller efficiency curves for both machines even though their IPLVs are different.</span></p> <p class="MsoNormal"><span style="font-size: 10pt; font-family: "sans-serif";"> </span></p> <p class="MsoNormal"><span style="font-size: 10pt; font-family: "sans-serif";">In order to overcome this issue, are you saying Rohini should get chiller performance data from each of the manufacturers and enter his own custom curves? I recall there was a discussion on that topic a few months back.</span></p> <p class="MsoNormal"><span style="font-size: 10pt; font-family:
"sans-serif";"> </span></p> <p class="MsoNormal"><span style="font-size: 10pt; font-family: "sans-serif";">Regards,</span></p> <p class="MsoNormal"><span style="font-size: 10pt; font-family: "sans-serif";">James Waechter Jr., P.E., CEM, LEED A.P.<br> Energy Engineer – Rocky Mountain Region<br> p 303 215 4062 | m 727 686 3248</span></p> <p class="MsoNormal"><b><span style="font-size: 10pt; font-family: "sans-serif";">McKinstry</span></b><span style="font-size: 10pt; font-family: "sans-serif";"><br> Consulting | Construction | Energy | Facility Services</span></p> <p class="MsoNormal"><span style="font-size: 10pt; font-family: "sans-serif";"><a rel="nofollow" target="_blank" href="http://www.mckinstry.com/"><span style="color: windowtext;">www.mckinstry.com</span></a> </span><span style="font-size: 11pt; font-family: "sans-serif";"></span></p> <p
class="MsoNormal"><span style="font-size: 10pt; font-family: "sans-serif";"> </span></p> <p class="MsoNormal"><span style="font-size: 10pt; font-family: "sans-serif";"> </span></p> <p class="MsoNormal"><span style="font-size: 10pt; font-family: "sans-serif";"> </span></p> <div> <div style="border-width: 1pt medium medium; border-style: solid none none; border-color: rgb(181, 196, 223) -moz-use-text-color -moz-use-text-color; padding: 3pt 0in 0in;"> <p class="MsoNormal"><b><span style="font-size: 10pt; font-family: "sans-serif";">From:</span></b><span style="font-size: 10pt; font-family: "sans-serif";"> equest-users-bounces@lists.onebuilding.org [mailto:equest-users-bounces@lists.onebuilding.org] <b>On Behalf Of </b>John Aulbach<br> <b>Sent:</b> Friday, February 25, 2011 9:41 AM<br> <b>To:</b> R B; eQUEST Users List<br> <b>Subject:</b> Re: [Equest-users] using IPLV in
eQuest</span></p> </div> </div> <p class="MsoNormal"> </p> <div> <div> <p class="MsoNormal">Rohini:</p> </div> <div> <p class="MsoNormal"> </p> </div> <div> <p class="MsoNormal">Won't happen. IPLV is a number which has one equation and 4 unknowns. Actually, three unknowns as you know the 100% point. You need a manufacturer's curve run at 85F constant condenser water temperature. Let eQuest do the curve bending after that. ARI curve won't work right.</p> </div> <div> <p class="MsoNormal"> </p> </div> <div> <p class="MsoNormal"> </p> <p class="MsoNormal"><span style="font-family: "sans-serif"; color: rgb(31, 73, 125);">John R. Aulbach, PE, CEM</span></p> <p class="MsoNormal"><span style="font-family: "sans-serif"; color: rgb(31, 73, 125);">Senior Energy Engineer</span></p> <div> <div> <div class="MsoNormal"><span style="font-family: "sans-serif"; color: rgb(23, 54, 93);">
<hr style="color: rgb(23, 54, 93);" align="left" width="30%" noshade="noshade" size="2"> </span></div> </div> </div> <p class="MsoNormal"><b><span style="font-family: "sans-serif"; font-variant: small-caps; color: navy;">Partner</span></b><b><span style="font-family: "sans-serif"; font-variant: small-caps; color: green;"> </span></b><b><span style="font-family: "sans-serif"; font-variant: small-caps; color: rgb(0, 102, 0);">Energy</span></b><b><span style="font-family: "sans-serif"; font-variant: small-caps; color: navy;"></span></b></p> <p class="MsoNormal"><span style="font-family: "sans-serif"; color: rgb(31, 73, 125);">1990 E. Grand Avenue, El Segundo, CA 90245<br> W: 888-826-1216, X254| D: 310-765-7295 | F: 310-817-2745</span></p> <p class="MsoNormal"><a rel="nofollow" target="_blank" href="http://www.ptrenergy.com/"><span style="font-family: "sans-serif"; color:
purple;">www.ptrenergy.com</span></a><span style="font-family: "sans-serif"; color: rgb(31, 73, 125);"> </span><a rel="nofollow" ymailto="mailto:%7C%20jaulbach@ptrenergy.com" target="_blank" href="mailto:%7C%20jaulbach@ptrenergy.com"><span style="font-family: "sans-serif";">| jaulbach@ptrenergy.com</span></a><span style="color: rgb(31, 73, 125);"></span></p> </div> <div> <p class="MsoNormal"> </p> <div> <div class="MsoNormal" style="text-align: center;" align="center"><span style="font-size: 10pt; font-family: "sans-serif";"> <hr align="center" width="100%" size="1"> </span></div> <p class="MsoNormal" style="margin-bottom: 12pt;"><b><span style="font-size: 10pt; font-family: "sans-serif";">From:</span></b><span style="font-size: 10pt; font-family: "sans-serif";"> R B <slv3sat@gmail.com><br> <b>To:</b> eQUEST Users List <equest-users@lists.onebuilding.org><br> <b>Sent:</b> Fri,
February 25, 2011 7:25:18 AM<br> <b>Subject:</b> [Equest-users] using IPLV in eQuest</span></p> <div> <p class="MsoNormal">Hi All, </p> </div> <div> <p class="MsoNormal">I would like to compare two screw chillers with same full load kW/ton and different IPLV kW/ton. I am using the full load number for the EIR. Where can the IPLV number be used? Is there some way to scale the performance curves to reflect different IPLV's?</p> </div> <div> <p class="MsoNormal">-Rohini</p> </div> </div> </div> </div> <p class="MsoNormal"> </p> <p class="MsoNormal"><br> This email is the property of McKinstry or one of its affiliates and may contain confidential and/or privileged information. If you are not the intended recipient or have received this e-mail in error please notify the sender immediately and delete this e-mail. Any unauthorized copying, disclosure or distribution of the material in this e-mail is strictly forbidden.
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