[Philsr]

The new TPR valve is discharging occasional water too. I am getting about a half gallon a day discharge.
It is not a temperature issue from what I have researched because I have kept the temperature on low.
A little history: I moved into the house recently. Saw water coming from the valve onto the floor of the garage and found out about replacing the TPR valve which I did so a few days ago.
I now am going to get a pressure gauge (Watts DP IWTG) at Home Depot and see what the highest reading is.
My main concern is that there is a danger here to be aware of. If the Temperature and Pressure relief valve is working by discharging, is there still any immediate danger to be aware of?
I have also read up on expansion tanks. Would they suddenly be something that is needed or maybe it was needed all along by the previous owner but they ignored this water discharge.
Any and all help will be appreicated!

Thanks!
Phil

[argaiu1017]

It is not temperature because your pilot will not be lit at all. If that is the case u would have to check your thermostat probe cause it calcifies, but it is not the problem.

What you might want to look into is what is the temperature set on the temperature and pressure relief valve cause it could be a 75psi or 125-150psi. With a high water pressure and thermal expansion on top of contained heated water would cause for discharge. Expansion tanks are not to relief excess water pressure, it is used because of a closed water system which results in thermal expansion.

[parttime]

I have also read up on expansion tanks. Would they suddenly be something that is needed or maybe it was needed all along by the previous owner but they ignored this water discharge.
Any and all help will be appreicated!

Thanks!
Phil

Phil, in my area the water company is installing check valves at their meters, creating a closed system. In cases here the expansion tank has worked. Good luck

[ma0641]

If a check valve is installed at the meter, you will need an expansion tank. I'd also check the main pressure reducing valve for the house supply. A lot of people blame the TPV when it is really the main reducer. Put a gage on the HW drain, it's a hose pipe thread. House pressure at the tank shouldn't exceed 75#. If it is over 75# or so, you need to try and adjust the valve or have it replaced.

[Philsr]

I will get a Watts gauge tomorrow and check pressures at both the front outside spigot and the water heater drain valve.
I'll report my findings...
There is a pressure regulator on my main line into the house by the way. I found out the hard way as I had to get a plumbing company out to fix the main water pipe feed into my house. The city water department damaged it when they were working on the water meter. Yes, I have a tort claim filed with my city to reimbuse the expenses.

Thanks to all for the responses, they are much appreciated!

Phil

[Philsr]

Some more questions in the meantime till I get my pressure readings:

1. what if I install an expansion tank and the T&P relief vave still leaks?

2. would a problem like this exist with one of the instant water heaters I see on the market now?

Thanks Again!

[ma0641]

I have found water leaking from TPV's for 3 reasons. Bad TPV, house pressure regulator too high, no expansion tank in a high pressure area. No expansion tank-20%, bad TPV-50%, bad house regulator 30%. You may be surprised testing water pressure at an unregulated sillcock. Depending on where you live, 120#+. Not sure why they still unregulate 1, my new house has all regulated and there is plenty of water. Instant HW heaters still use city supply at no different pressure.

[Philsr]

Hello,
It turns out that my water pressure into the house was 140psi - yikes!
I got a new pressure regulator installed by a plumber. Now all is fine with the water heater.

Thanks for all the responses!

[ma0641]

Hey Phil, glad to hear you fixed the problem. As I indicated in my post, 30% or more of the time people have "leaking TPV' it's the main regulator.