I put in a new bathroom right by my water heater, about 25 ft of hot and cold pex line. Ever since The day I turned on the valves to do a leak test, I've had a very slow drip from my temperature pressure valve on my water heater. It's only a drip every few hours, creating very little water, but it has been consistently dripping. I'm wondering why this is happening. Any thoughts?

  • What is the pressure in your house? Do you have a pressure reducer to lower city mains pressure to the proper valve for residential plumbing? – Jim Stewart Mar 17 '19 at 12:34
  • I have a private well, typically pressurized at around 40-50 psi at the bladder tank – BigLake Mar 17 '19 at 12:51

I often pop the T&P a few times quickly and tap the rod to seat the valve firmly. It works more often than not. Also when you drained your tank, did you open the T&P for relief air? If so, next time don't. I see guys opening it to drain the tank. Then I see guys replacing leaky T&P valves.

  • I did not open it, just noticed it dripping. I'll try the toilet jiggle method lol – BigLake Mar 19 '19 at 1:07
  • 2
    It's just a rubber gasket on a brass seat with a heavy spring pushing on it. Popping it clears some debris on firmly taping the pip in helps to seat the valve deeper hopefully enough to seal fully. The rubber gets hard and tapping it helps to depress it. – Joe Fala Mar 19 '19 at 1:17

When you turned the water back on after your plumbing work you may have mobilized sediment in the tank or lines and this is interfering with the sealing of the TPV. You could briefly open the valve manually with the lever to try to clear it. After doing this it would take a while to see if the leak was stopped.

Of course, it could get stuck open or leak worse. Naturally you'd use a bucket under the relief outlet unless it goes directly into a drain or outside.

Perhaps you should have a new valve on hand when you start dealing with this. You might have to replace the TP relief valve.

  • I did try manually clearing it, I also flushed the tank about a month ago in preparation for the bathroom project, of course there could still be residual sediment. I guess it baffled me because I figured the drawdown off the tank when I opened the new valves would reduce the pressure, guess things don't always do what you would assume lol – BigLake Mar 17 '19 at 12:54

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.