Water Supply & DistributionQuestion 42 of 120
A commercial kitchen is being piped with solenoid-operated quick-closing valves on the dishwasher and ice machine supplies. What does the code require on those branches?
a.A larger supply pipe to slow the water velocity
b.Approved water hammer arrestors sized and located per the manufacturer's instructions
c.A check valve immediately upstream of each valve
d.A vacuum breaker on each supply branch
Explanation
Quick-closing valves stop flow almost instantly and convert momentum into a pressure spike, so the code requires approved water hammer arrestors on those branches. Upsizing pipe reduces velocity somewhat but does not satisfy the arrestor requirement. A check valve does not absorb the shock wave, and a vacuum breaker addresses back-siphonage, which is a different problem entirely.
Law Reference: IPC §604.9Practice all 120 questions free — no signup required.
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