Fixtures & Water HeatersQuestion 168 of 360
The discharge pipe served by a water heater T&P relief valve must be sized so that it is:
a.one pipe size smaller than the valve outlet
b.sized for the water heater inlet
c.not smaller than the diameter of the valve outlet
d.always 3/4 inch regardless of the valve
Explanation
The relief discharge pipe must be at least the full size of the T&P valve outlet, with no reduction along its length. Reducing the pipe would restrict flow during a discharge event and defeat the safety function. It must also serve only one relief valve.
Law Reference: 2022 California Plumbing Code (CPC) §608.5Practice all 360 questions free — no signup required.
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