eQUEST - serios trouble with LEED review

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Hi Everyone,

I got a review comment that got me in big trouble and I can't find the
solution yet.

May be there is no solution for this in eQUEST....!

I rate this forum as the very best address for difficulties with eQUEST and
LEED EAc1 simulation.

So please give me some guidance and feel free to test the model attached.

Here are the two comments of the reviewer.

"It appears as if the pumps and circulation loops were not modeled correctly
for the Baseline Case. It appears based on the PS-C reports that there is
only one primary chilled water pump and one condenser water pump for the
Baseline Case. However, ASHRAE 90.1 Section G3.1.11 requires that each
chiller be modeled with separate condenser water and chilled water pumps
interlocked to operate with each associated chiller. Please model two
primary chilled water pumps and two primary condenser water pumps in
accordance with Section G3.1.11. Also update the chilled water valves to
two-way valves so that the secondary chilled water loop operates as a
variable flow loop with pumps riding the curve. Provide updated PS-C reports
confirming that the changes have been made."

"It is unclear why the pump flow for the secondary chilled water loop is so
much larger than that of the primary chilled water loop when the temperature
differential for both loops is expected to be the same. It also appears
based on the outputs in PS-C that the secondary chilled water loop is
operated at the same load for every hour that it is on even though it is a
variable speed pump. Please update the secondary chilled water loop flow to
be consistent with the primary chilled water loop flow, and confirm that the
secondary chilled water loop is operating as a variable flow loop."

I have to say:

I didn't see any equest-model modeled with separate condenser water and
chilled water pumps interlocked to operate with each associated chiller.

I manually resized the boilers and chillers with reference to SS-D report,
because auto sizing of eQUEST generated capacities that were double the size
of SS-D report. Resizing of the volume flow of secondary loop of chillers
according to primary loop of chillers generated warning messages but changed
nothing.

Heinrich

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