Water Supply & DistributionQuestion 9 of 360
A quick-closing solenoid valve on a commercial dishwasher is causing banging pipes. What does the code require to control the resulting water hammer?
a.An approved water hammer arrestor installed near the quick-closing valve
b.Increasing the system pressure to 90 psi
c.Removing all check valves from the system
d.Replacing copper with cast iron
Explanation
Quick-closing valves generate water hammer, and the code requires approved water hammer arrestors, typically installed near the quick-closing valve. Raising pressure would worsen the shock, removing check valves does not address the surge, and switching to cast iron is not the code remedy for water hammer on a pressurized water line.
Law Reference: 2022 California Plumbing Code (CPC) §609.10Practice all 360 questions free — no signup required.
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