Water – Proper Setup for Water Heater Gas and T&P Relief Valve

water-heater

I will be replacing my water heater soon and want to get two clarifications.

First, is the only issue with the current gas line that a sediment trap is missing or is there anything else that needs to be done to bring it up to code?

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My second question would be the piping for the T&P and what our the options. I have read the wording in the code, but I am unclear what should be done in a finished basement with limits options for draining. This is the setup that is currently there. The pipe exits the utility room and run behind the wall before dropping into our drain.

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Best Answer

All backed up

The primary problem with your setup is that what you have right now is a sanitary hazard, as there is no air gap preventing sewage from backing up into the T&P discharge line. A standard water-softener or standpipe type air gap fitting can be used for this task, though, and is inexpensively available wherever plumbing supplies are sold.

The rest of the setup, though, is OK; the cellular core ABS pipe is fine since it's downstream of the standpipe, and discharging T&P relief water to a standpipe via an air gap is an acceptable means of T&P discharge, as per IRC P2804.6.1 point 5 which permits discharge of T&P relief water to a "waste receptor", which by Code can be a hub drain, standpipe, floor/mop sink, or floor drain.