Water Supply & DistributionQuestion 25 of 360
A residential water heater is 55 feet of developed pipe run from the farthest bathroom. Using standard practice, which change would most directly reduce the long wait for hot water without adding a recirculation pump?
a.Reducing the volume of water in the hot branch by using a smaller-diameter dedicated run within code limits
b.Increasing the pipe diameter as much as possible
c.Lowering the water heater thermostat
d.Removing all pipe insulation
Explanation
The wait for hot water is driven by the volume of cooled water that must be cleared; using an appropriately smaller-diameter dedicated hot branch (within code sizing limits) reduces that stored volume and shortens the wait. Oversizing the pipe increases stored volume, lowering the thermostat delays useful temperature, and removing insulation increases heat loss.
Law Reference: 2022 California Plumbing Code (CPC) §610.0Practice all 360 questions free — no signup required.
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