Systems & CodeQuestion 38 of 110
A temperature-and-pressure (T and P) relief valve on a water heater is rated to open at 210 F and 150 psi. What is the required disposition of its discharge pipe?
a.Trapped and vented to the drain
b.Run full-size to within 6-24 in of the floor with no trap or valve
c.Reduced one size and terminated outside above grade
d.Connected to the recirculation return
Explanation
The T and P discharge must be full pipe size, contain no valves or traps, and terminate 6 to 24 in above the floor or an approved receptor so a discharge is visible and cannot be blocked. A trap would hold water and corrode; a valve could be shut and defeat the safety device. This prevents a tank from becoming a pressure vessel.
Law Reference: UPC §608.3Practice all 110 questions free — no signup required.
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