Can't force pump power to Zero?

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I've got a fairly simple primary/secondary chilled water system with a
waterside economizer chiller.

I've already got a secondary chilled water pump circulating primary
chilled water to the systems in my proposed building, and it does double
duty as pumping through the heat exchanger in my proposed design. So
the chilled water pump that I've set up for the waterside economizer (to
regulate maximum flow) really has Zero power consumption.

However, when I set the KW to 0.00 for this pump, eQuest is STILL
auto-sizing something and forcing the KW to around 32 KW. I even set
the efficiencies to 1.0 to see if that made a difference (doesn't). I'm
not sure if it has something to do with the warning about the pump not
being able to match system flow at the minimum required head...but why
can't I force this KW to 0??

Has anyone ever run into this? Here's a screenshot of my input for that
pump and the PV-A output. Thanks in advance!

James Hansen, PE, LEED AP

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