Water Supply & DistributionQuestion 6 of 360
A plumber connects PEX tubing to a residential water heater. What does the code require at the hot-water outlet connection?
a.PEX may be connected directly to the water heater nipple
b.PEX must not be installed within the first 18 inches of piping connected to a water heater; a metallic connector is used for that section
c.PEX must be within 6 inches of the flue
d.PEX is prohibited anywhere in potable systems
Explanation
Because of high outlet temperatures, PEX is not permitted within the first 18 inches of piping connected to a water heater, so a metallic (for example copper) connector is used at that point. Direct connection at the nipple is not allowed, and PEX is otherwise an approved potable water material, so the prohibition and 6-inch flue claims are wrong.
Law Reference: 2022 California Plumbing Code (CPC) §604.1Practice all 360 questions free — no signup required.
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