Modeling a Dual Duct with Neutral Deck

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I am trying to model a Texas Multizone System using the Dual Duct System
with no Heating Coil on the Hot Deck. Therefore the Hot Deck is simply a
neutral Deck that simply passes the mixed air conditions. The Cooling Coil
maintains the cold deck at 55 F. To capture the electric heat that exist
after the mixing boxes of each zone, I have specified electric base board

Ideally, in the winter, this system should provide a mixture of neutral deck
and cold deck to the interior zones and 100% neutral deck to the perimeter
zones. The perimeter zones would then meet the set point using the
baseboard heaters.

In the summer, both the core and perimeter zones would be provided a mixture
of neutral and cold deck. There should be no reheat happening.

Unfortunately, a large amount of reheat is being shown and I don't
understand why. The .sim file states that the "MIN_FLOW-SOURCE" for all
constant volume mixing boxes is the COLD-DUCT. It seems that all the air in
the summer and the winter is provided to the zones from the cold deck so
there is an excessive amount of reheat.

How can I configure the Dual Duct system to capture a cold/neutral deck. I
don't want to use the Multizone Fan System (MZS) because one of the energy
conservation measures is to evaluate variable flow control but the MZS can
only due constant flow.

Thanks in advance.


Rachel Michaels's picture
Joined: 2011-09-30
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