<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;color:#000000;"><pre>Gary:<br><br>In reference to your e-mail below, I also have created custom heating and cooling EIR curves for eQuest.<br><br>I downloaded the performance tables from the Daikin site, but could not find RPM data<br>or the minimum cycling part load ratio performance. I heard second hand from the local Daikin<br>distributor that the minimum load on the condenser is 50% of rated capacity. Is this your experience?<br><br>Could you tell me where to find the RPM and part load ratio performance? I am modeling the REYQ-PTJU<br>Heat Recovery system.<br><br>Thank you,<br><br>Paul Diglio<br><br>Dave,<br> <br>I have heard the rumors about a VRV system being added to DOE 2.2 in the<br>future as well. The last time I heard the rumor, the package was<br>supposed to be out this spring. As is
true of the entire software<br>industry, that likely means it will appear sometime in the year 2012.<br>(Predicted release date + 3 years = Actual release date)<br> <br>I hope there is someone on here who can better clarify the date and<br>progress of the package...<br> <br>To your second point, our office has been modeling Daikin VRV systems in<br>eQuest for a few months now. Don't get too excited... we haven't<br>actually installed one yet so we have no real data with which to prove<br>that we are modeling the systems correctly. That said, we also have only<br>modeled their "Heat-Pump" line and not their "Energy Recovery" line,<br>which allows simultaneous heating and cooling between zones.<br> <br>We created custom curves with which to model the compressor by taking<br>Daikin Engineering data out of Daikin tables and plugging it into<br>eQuest. Then we model the system using the "Packaged Single Zone" system<br>type. We set the Indoor fan to
two-speed and gave it a very light static<br>pressure, due to the fact that the system has multiple indoor fans with<br>low static vs. one fan with lots of static. We hard-keyed the CFMs, the<br>rated capacities, the compressor RPMs, low and high, the minimum cycling<br>part load ratio, the cooling (and heating) EIR, and set the compressor<br>to variable speed type and gave it a minimum unload ratio, again, all<br>from Daikin literature. We used eQuest's default low-speed EIR curve.<br>The capacity curve and the EIR curves we custom-created using eQuest and<br>Daikin data.<br> <br>The results seem logical. Again, it's hard to prove that things are<br>dead-on because we have no real building to compare our results to.<br>Hopefully, though, that will give you a place to start.<br> <br>I am not confident that I am modeling defrost correctly, and winter<br>results in general seem more sketchy. I am using eQuest's default<br>defrost running time fraction,
which I assume is more pertinent to<br>standard unitary equipment. Daikin's defrost seems more efficient. It<br>also doesn't help that Daikin doesn't use either resistive or reverse<br>cycle for their defrost strategy... it's actually hot-gas bypass.<br> <br>One last thing, all of the engineering data that we obtained from Daikin<br><span>was published on their website, <a target="_blank" href="http://www.daikinac.com">www.daikinac.com</a>.</span><br> <br>I hope this helps. Good luck!<br><br>Gary Schrader<br>Engineer I<br><br>TAC<br>16011 College Blvd, Suite 212<br>Lenexa, KS 66219<br><br><br>Direct: +1 <br>Fax: +1 913-469-0206 <br>Mobile: +1 913-217-8068 <br>Email: <a href="http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding.org">Gary.Schrader at tac.com</a> <br><span>Web: <a target="_blank" href="http://www.tac.com">www.tac.com</a> <</span><a href="http://www.tac.com/">http://www.tac.com/</a>> <br></pre></div></body></html>