An eQUEST output question.

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Hello All,
Here is a "sim" output from the hospital bldg I am modelling.
The secondary CHW pump has a VFD on it and I would think that the flow would
be proportional to speed and the pump would spent some time in the lower
load ranges rather being in > 80% load range.

(*Although I do not know as to how eQUEST comes up with the speed to match
with flows - my presumption being that the flows are being derived from the
loads and delta-T. The constant speed pumps cycles on and off to get deliver
the load and VFD equipped pump varies the speed of the pump to regulate the
flow to satisfy the load*)

Why is the speed hours not consistent with the flow hours? I am also
not limiting the speed of the pump in any way to below 80% range.

Please advise.

Thanks in Advance,
Kazim Mirza

Kazim Mirza's picture
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Joined: 2011-09-30
Reputation: 0
For the VFD to take effect, the cooling coil valve has to be two-way. Default in eQuest is three-way. See if that is the issue. -Rohini
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R B
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Joined: 2011-09-30
Reputation: 4