Design & SizingQuestion 5 of 110
A system has 62 psi at the meter. It must overcome 22 psi of elevation, 14 psi of friction loss in the piping, and deliver a fixture that requires 8 psi minimum flow pressure. What residual pressure remains at the fixture?
a.18 psi
b.8 psi
c.14 psi
d.16 psi
Explanation
Residual = 62 - 22 (elevation) - 14 (friction) = 26 psi available at the fixture, which exceeds the 8 psi required, leaving 26 - 8 = 18 psi of margin. The design works because the delivered 26 psi is greater than the 8 psi minimum. The pressure budget must always balance supply against elevation, friction, and fixture demand.
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