Water Supply & DistributionQuestion 36 of 360
A pressure-reducing valve is set to deliver 65 psi downstream from a 110 psi street pressure. On a closed system, what additional device is commonly required to accompany the PRV?
a.A second meter
b.A larger service
c.A gate valve only
d.Thermal expansion control (expansion tank), because the check in the PRV closes the system
Explanation
Because a PRV typically includes or creates a check that closes the system, thermal expansion control such as an expansion tank is commonly required to absorb pressure rise from water heating. A second meter, larger service, or a gate valve alone would not relieve thermal expansion in the closed system.
Law Reference: 2022 California Plumbing Code (CPC) §608.2Practice all 360 questions free — no signup required.
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