I want to add a drain line from my water softener to the existing line that is already run through the wall from my hot water heater emergency drain line.(with the pressure relief valve)
I just want to tie into it with a "T" so they can both use that existing line and not reroute or add anything.
Does anyone see any potential problem?
Thanks!!

Not a pro but my understanding is your WH T&P drain line cannot be piped to the sewer, it needs to be piped to a location where you can visually see it is dripping so if that happens you can take remedial action. Having another drain tie into it defeats that purpose I would think.

you may NOT combine the two 'pipes'


the T-PRV discharge pipe is NOT a drain and MUST be independantly run to a visible point of 'safe discharge'


the key words being: independant - visible - safe

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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638