<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML><HEAD>
<META http-equiv=Content-Type content="text/html; charset=iso-8859-1">
<META content="MSHTML 6.00.2900.3562" name=GENERATOR></HEAD>
<BODY>
<DIV><SPAN class=189424018-15062009><FONT face=Arial size=2>Equest
Users:</FONT></SPAN></DIV>
<DIV><SPAN class=189424018-15062009><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=189424018-15062009><FONT face=Arial size=2>I'm modeling a
single story building with 2 packaged rooftop HP units in Las Vegas. I have
allowed the program to autosize airflow and cooling and heating
capacities.</FONT></SPAN></DIV>
<DIV><SPAN class=189424018-15062009><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=189424018-15062009><FONT face=Arial size=2>I'm guessing that
the high amount of underheated hours is due to the fact that the PSZ system
type uses only one of its assigned zones as the control for constant volume
airflow. I have designated the control zone as the zone with the
highest internal loads. This works OK in cooling mode, though, I
still have about 400 undercooled hours. But in heating mode, the zone
with the highest internal loads does not need as much heat as the other
zones. Since it's a constant volume system and the control zone is saying
"no heat needed", the rest of the zones are not getting any heat. Is that
right??</FONT></SPAN></DIV>
<DIV><SPAN class=189424018-15062009><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=189424018-15062009><FONT face=Arial size=2>Following through
with the assumption above, I tried to increase the minimum cfm/sqft on zone
level to 0.5, but my underheated hours went up.</FONT></SPAN></DIV>
<DIV><SPAN class=189424018-15062009><FONT face=Arial size=2>I only manage
to decrease unmet heating hours after I increase
the cfm on the system level to about 5 times what Trane
sizes. </FONT></SPAN></DIV>
<DIV><SPAN class=189424018-15062009><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=189424018-15062009><FONT face=Arial size=2>Can someone help me
out here?</FONT></SPAN></DIV>
<DIV><SPAN class=189424018-15062009><FONT face=Arial size=2>Thank
you!!</FONT></SPAN></DIV>
<DIV><SPAN class=189424018-15062009><FONT face=Arial
size=2>Linda</FONT></SPAN></DIV>
<DIV><SPAN class=189424018-15062009><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV align=left><IMG
alt="
Linda Lam, LEED® AP
WSP Flack + Kurtz
405 Howard Street, Suite 500
San Francisco, CA 94105
Direct: 415.402.5813
Main Tel: 415.398.3833
Fax: 415.433.5311
website: http://www.wspfk.com
vCard: http://vcards.wspfk.com/vcardloader.php?filename=flackkurtz-linda-lam-wspfk-com-1227040073.vcf
image: "
src="http://vcards.wspfk.com/usercard.php?filename=flackkurtz-linda-lam-wspfk-com-1227040073.png"
align=absMiddle useMap=#flackkurtz-linda-lam-wspfk-com-1227040073 border=0
nosend="1">
<STYLE>
a {color: 1D88F6;}
</STYLE>
<MAP name=flackkurtz-linda-lam-wspfk-com-1227040073><AREA shape=RECT
target=_blank coords=401,9,458,31 href="http://www.wspfk.com"><AREA shape=RECT
target=_blank coords=458,9,503,31
href="http://vcards.wspfk.com/vcardloader.php?filename=flackkurtz-linda-lam-wspfk-com-1227040073.vcf"><AREA
shape=RECT target=_blank coords=503,9,536,31
href="http://maps.google.com/maps?f=q&hl=en&geocode=&q=405+Howard+Street,+San+Francisco,+CA+94105&sll=40.754409,-73.988972&sspn=0.019083,0.032616&ie=UTF8&ll=37.79032,-122.395163&spn=0.019908,0.032616&z=15&iwloc=addr"><AREA
shape=RECT target=_blank coords=536,9,578,31
href="mailto:linda.lam@wspfk.com"><AREA shape=RECT target=_blank
coords=0,31,591,161 href="http://www.wspfk.com"></MAP></DIV>
<DIV> </DIV></BODY></HTML>