Water Supply & DistributionQuestion 18 of 360
A flushometer (flush valve) water closet is being served. Compared with a flush-tank water closet, what does the flushometer require from the water distribution design?
a.Lower flow but higher static pressure only
b.A higher instantaneous flow rate and adequate residual (flow) pressure at the valve
c.No special consideration
d.A smaller supply branch than a lavatory
Explanation
A flushometer discharges a high instantaneous flow and needs adequate residual pressure (commonly on the order of 15 to 25 psi) and a larger branch than a flush-tank closet. It does not merely need higher static pressure with low flow, it always requires special consideration, and its branch is larger, not smaller, than a lavatory branch.
Law Reference: 2022 California Plumbing Code (CPC) §610.0Practice all 360 questions free — no signup required.
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