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<DIV><FONT face=Arial size=2>I am modeling a building with packaged gas/electric
rooftop units with Carrier System 3 (previously Parker) zone dampers and bypass.
I am getting a huge number of hours with loads not met and I'm thinking it's due
to the model using just the one control zone to determine the operating mode of
the unit, instead of the combination of "majority rules" and "zone of greatest
demand" logic the actual system uses. Does anyone have a method of better
simulating the actual equipment operation which accounts for the system's
ability to reverse modes if some zones, in my case other than the specified
control zone, are calling for the opposite? Is the ceiling bypass VAV model more
similar to this actual system? I'm thinking maybe not as it resets leaving air
temperature only on zone of greatest cooling demand. I'm confident the
system design will maintain comfort conditions in the various zones even if the
unit has to reverse modes occasionally, but the modeling is for LEED which
restricts how many unmet load hours you can have. All thoughts and experience on
this subject would be appreciated, and thanks for your replies to my other
recent messages.</FONT></DIV>
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<DIV><FONT face=Arial size=2>Rick Routh</FONT></DIV>
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