Water Supply & DistributionQuestion 49 of 360
A main serves 60 WSFU predominantly through flushometer valves. Using a flush-valve Hunter conversion, this is about 51 gpm. If you had mistakenly used the flush-tank curve, you would get a much lower gpm. Why does the flush-valve column give a higher demand for the same fixture-unit count?
a.Because flush valves draw a high instantaneous flow, so the same fixture-unit load converts to a higher peak gpm
b.Because flush valves use no water
c.Because fixture units differ from gpm at random
d.Because flush valves reduce demand
Explanation
Flushometer valves draw a high instantaneous flow, so the flush-valve conversion curve yields a higher peak gpm for the same fixture-unit count than the flush-tank curve. Flush valves clearly use water, the conversion is not random, and they raise, not reduce, peak demand.
Law Reference: 2022 California Plumbing Code (CPC) §610.0Practice all 360 questions free — no signup required.
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