TPR Valve failure

[Happydaddybrian]

I have the problem of my TPR valve beginning to leak after about 6-9 months of installing a new one. After replacing it last, I lowered the temp of my water heater from 120 to 113 hoping to see an improvement. I found out this morning that it's beginning to leak again. I don't recall when I last replaced it, but I know it shouldn't be fail this frequently.

My original hot water heater in this house had a pressure relief tank installed so I replaced it with a new one when I replaced the water heater several years ago. I was beginning to see the same problem with the TPR valves failing however before replacing the old equipment.

Any thoughts?

 

[SHEPLMBR]

Do you have an expansion tank on the water heater?

 

[Happydaddybrian]

Do you have an expansion tank on the water heater?

Yes. Replaced it when the water heater was replaced a few years ago.

 

[Jeff Handy]

Maybe the incoming city water pressure is too high?
Or it spikes occasionally, which could make the heater valve start to dribble.
And water heater sediment can get into the TPR valve and cause dribbles.

Flush the water heater, then operate the TPR valve several times, dumping into a bucket or whatever.
That would clear out crud in the TPR valve of the heater.

Test your incoming pressure with a screw on gauge, and maybe add a pressure reducing valve if you don’t already have one, set to approx 70 psi.

If you already have a PRV, it might be defective.

And maybe your expansion tank has lost its charge, or needs proper air volume?

What is the water heater TPR valve psi setting?
They are usually pretty high, but maybe your new one is too low?

 

[Diehard]

Are you sure that the expansion tank was filled with the recommended air pressure(water service pressure) PRIOR to being installed in the piping?

You could attach a pressure gauge(with a memory needle) to your water heater drain, to check how high the pressure actually gets. The T&P Relief valve may be doing what it was designed to do.

 

[Solar]

I have the problem of my TPR valve beginning to leak after about 6-9 months of installing a new one. After replacing it last, I lowered the temp of my water heater from 120 to 113 hoping to see an improvement. I found out this morning that it's beginning to leak again. I don't recall when I last replaced it, but I know it shouldn't be fail this frequently.

My original hot water heater in this house had a pressure relief tank installed so I replaced it with a new one when I replaced the water heater several years ago. I was beginning to see the same problem with the TPR valves failing however before replacing the old equipment.

Any thoughts?

I have the problem of my TPR valve beginning to leak after about 6-9 months of installing a new one. After replacing it last, I lowered the temp of my water heater from 120 to 113 hoping to see an improvement. I found out this morning that it's beginning to leak again. I don't recall when I last replaced it, but I know it shouldn't be fail this frequently.

My original hot water heater in this house had a pressure relief tank installed so I replaced it with a new one when I replaced the water heater several years ago. I was beginning to see the same problem with the TPR valves failing however before replacing the old equipment.

Any thoughts?

Hello Brian,

Here are a few checks that you can do:

Check the tank input pressure water line.

Make sure that the pressure does not go higher than 65 psi.

Flush and drain your hot water tank very well.

Install a pressure regulator in the cold water inlet side.

If you still have a problem, install an expansion tank.

Also, do not pull or push on the PRV. By doing this, you can make this PRV valve fail.

Replace with a new PRV.

If you do these things, you will no longer have this problem.

I hope that this information is helpful to you. Please let me know how this works for you.

Bob

 

[Diehard]

With all due respect, the above comments are all over the place.

I suggest you take a logical approach and test things out one step at a time.

Don't start replacing things unless it has been determine to be necessary.

If you don't already know how to properly check the air pressure in your expansion tank, google it and/or ask.(It has to be isolated from the water pressure when you check it.)

 

[Diehard]

One of the first things that should be verified is the SIZE of the expansion tank.
What size is your water heater?
What size is your expansion tank?
Do you have an idea of your incoming water pressure?
(The initial pressure setting in the expansion tank should closely match your incoming water service.)

 

[wood4d]

I never open the tprv because they always leak after that. Also hot water heaters should be set around 140. You cant clean your dishes with water that cold. If tprv's are failing there is something else wrong. Is your prtank your expansion tank or is it a round metal cylinder attached in the floor above?

 

[Mikey]

What Diehard said in #5. If there's a check valve in the main line to your house, then the water heater might be causing enough expansion during normal cycles to make the PRV drip.

 

[Diehard]

What Diehard said in #5. If there's a check valve in the main line to your house, then the water heater might be causing enough expansion during normal cycles to make the PRV drip.

True!
Looking back, I don't think we established if he does or doesn't have any type of check valve in his main line.