Fixtures & Water HeatersQuestion 171 of 360
A plumber is routing the discharge from a water heater T&P valve. Which installation is code-compliant?
a.Install a ball valve in the line for easy testing
b.Run the pipe full-size with no valve between the T&P valve and the outlet
c.Reduce the pipe to 1/2 inch to fit through the wall
d.Trap the line to catch drips before it exits
Explanation
No shutoff or check valve may be placed between the relief valve and the discharge outlet, because a closed valve would block emergency relief. The pipe stays full-size and untrapped, draining by gravity to an approved point. These rules keep the safety discharge always open.
Law Reference: 2022 California Plumbing Code (CPC) §608.5Practice all 360 questions free — no signup required.
Related questions on this topic
- The discharge pipe served by a water heater T&P relief valve must be sized so that it is:
- A T&P relief valve discharge pipe terminating outside the building must end how far above the ground or receptor?
- Which condition is required at the terminal end of a water heater relief valve discharge pipe?
- How must a water heater relief valve discharge pipe flow to its point of discharge?
- The material used for a water heater T&P relief valve discharge pipe must be:
- When a T&P relief discharge terminates to an indoor location such as a floor drain or pan, an air gap is required. Where must that air gap be located?
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