Water Supply & DistributionQuestion 12 of 360
A residence has a closed water supply system because the water meter contains a check valve and a pressure regulator. As the water heater heats water, pressure spikes dangerously. What does the code require to relieve this?
a.A larger cold water main
b.Removing the pressure regulator
c.A hose bibb left open
d.A means of thermal expansion control, such as an expansion tank
Explanation
In a closed system, heated water cannot expand back toward the main, so the code requires thermal expansion control such as an expansion tank or approved relief device. Enlarging the main does not absorb expansion, removing the regulator defeats pressure control, and leaving a hose bibb open is not a permanent code-compliant solution.
Law Reference: 2022 California Plumbing Code (CPC) §608.3Practice all 360 questions free — no signup required.
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