What is this line for. Small copper T off cold water supply to water heater? Changes to PVC and then directly into of water heater pain drainage. Simple setup. No expansion tank. No hot water recirculation.
Can’t see well enough from your photos but from here I’d guess it’s a trap primer.
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My wag it is a thermal expansion device. Was there a shut off valve incorporated? That’s another possibility.
That’s what I was thinking too. There is likely backflow prevention on the main on this house, so I would think it would need an expansion tank. There’s no additional shut off for it. The hardware at the T connection just didn’t seem to be large enough to incorporate an expansion valve internally. Smaller than a TPR. Anyways, Thanks.
It’s a small line like a trap primer, but there would be no need for that. There are no P-traps on a water heater. I did find this though. looks like it is a substitute for an expansion tank called a Thermal Expansion Relief Valve.
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I came across a plumbing setup that has left me curious, and I’m eager to tap into the collective knowledge here. The situation involves a small copper T branching off the cold water supply to a water heater. From there, the setup transitions to PVC and directly connects to the water heater’s drain valve. It’s a simple configuration, but I’m wondering about the reasoning behind this approach. Is this an acceptable practice?
I can not see how the plumbing line would have the ability to become a thermal expansion device that would regulate pressure in the water heater but I could be mistaken. Where does the end of the plumbing line go?
If you follow at the domestic potable cold water supply line tap, the piping it is linked to water heater’s safety pan plumbed to the same vertical drain line. I think it is a trap primers used in plumbing systems to prevent floor drain traps from losing their water seal by evaporation.
How old is the home?
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Agree. Hard to confirm with the photos, but those are reasonable conclusions based on what we can see and the OP’s description.
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I concur, Lon. To become a thermal expansion device there should be a visible device. All I can see is the safety pan plumbed into the same PVC drainage line from that tapped copper domestic supply line.
The TPRV tube looks suspect.