Water Supply & DistributionQuestion 48 of 360
A carbonated beverage dispenser connects to the potable water supply, and CO2 can back-feed into copper tubing, forming corrosive carbonic acid that leaches copper. What protection does the code require?
a.A single check valve of any material
b.No protection needed
c.A gate valve
d.A backflow preventer specifically listed for carbonated beverage dispensers (and non-copper tubing after the device)
Explanation
Carbonated dispensers require a backflow preventer listed for that use, and the tubing between the device and dispenser must be a material other than copper to avoid carbonic acid leaching copper. A plain single check, no protection, or a gate valve does not address the specific carbonation hazard and copper corrosion risk.
Law Reference: 2022 California Plumbing Code (CPC) §603.0Practice all 360 questions free — no signup required.
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