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Discussion Starter #1
It seems like I just bought the new one but it has been a couple of years already. I noticed the ground was wet where the pressure release pipe goes out and yep, it was trickling out hot water. Looks like it had been for 3 or 4 days. In my entire life history with hot water heaters I have never ever had to replace that pressure relief valve,,,,,,UNTIL NOW. It now appears to have become a common thing to fail. It is so common in fact that my local back water lumber and supplies place had several of them in stock.

What concerns me now is that my new one looks absolutely identical to my old one down to the lettering on it. I have to wonder how long this one will last. At least it didn't flood my closet, AC and hallway because it has pvc pipe down through the floor and drains out of the vinyl siding on the house through some trap door looking tin gadget.
 

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Made overseas?
Almost everything is now, and almost everything fails, over and over and over.
I'm about to have to install my fourth dishwasher in 16 years. "Assembled in America" isn't the same as "Made in USA".
 

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At least you had one. When I first moved into my house I did a thorough inspection and discovered that someone had replaced the pressure valve with a pipe plug. And the water heater was over 10 years old!
 

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Do you have a expansion tank installed by the heater? If so, it could be bad. The process of heating water creates thermal expansion. The water will expand and if no tank, it will push open the relief valve to bleed down the pressure. there could be nothing wrong with your relief valve, but if left to bleed out, it will eventually ruin the seat and will need replaced.
 

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Discussion Starter #6 (Edited)
Do you have a expansion tank installed by the heater? If so, it could be bad. The process of heating water creates thermal expansion. The water will expand and if no tank, it will push open the relief valve to bleed down the pressure. there could be nothing wrong with your relief valve, but if left to bleed out, it will eventually ruin the seat and will need replaced.
No expansion tank. The instructions just said to leave a tap open as the unit filled up the first time to release the excess air pressure filling it caused. I run the hot water several times every day anyway washing my hands and face, shaving, taking showers, washing individual cups or dishes so I don't think the tank had any excessive pressure. I opened the pressure valve anyway over the 24 hours or so it took the first fill of water to get hot just to be sure it was ok.

I compared the old release lever with the new one and the old pressure spring felt weaker than the new one. I think that was the source of the leak. The bad thing is that since my new one looks exactly like the old one, I am fairly confident that it won't last long either. Maybe I should check around and see if somebody makes a superior valve but I had to have one quick so I could turn the water back on.

I have my water temp set low so the water never gets hot enough to activate the thermostat in that thing. Actual water pressure in the lines is on the low side since my "water company" tapped into my feed line in front of the meter to feed another person's house. I wanted him to extend the main since I was at the end of the main line but he refused to do that. The other house's pressure is low too and if we are both running our showers we can tell immediately because it gets lower still.
 

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No expansion tank. The instructions just said to leave a tap open as the unit filled up the first time to release the excess air pressure filling it caused. I run the hot water several times every day anyway washing my hands and face, shaving, taking showers, washing individual cups or dishes so I don't think the tank had any excessive pressure. I opened the pressure valve anyway over the 24 hours or so it took the first fill of water to get hot just to be sure it was ok.

I compared the old release lever with the new one and the old pressure spring felt weaker than the new one. I think that was the source of the leak. The bad thing is that since my new one looks exactly like the old one, I am fairly confident that it won't last long either. Maybe I should check around and see if somebody makes a superior valve but I had to have one quick so I could turn the water back on.

I have my water temp set low so the water never gets hot enough to activate the thermostat in that thing. Actual water pressure in the lines is on the low side since my "water company" tapped into my feed line in front of the meter to feed another person's house. I wanted him to extend the main since I was at the end of the main line but he refused to do that. The other house's pressure is low too and if we are both running our showers we can tell immediately because it gets lower still.
Is this a gas or electric tank?
 

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We had a similar issue recently. Every day the pressure relief valve let out hot water. Long story short: it turned out
to be the house pressure regulator was bad (only a few years old "best on the market") and caused extremely high
pressure in the house (it would fluctuate), filling up the expansion tank, then, when the water had no where else to
go, it blew through the hot water relief valve. So be aware that what you are seeing may be just a sympton, not
the real problem.
 

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Any time that you increase the temp of water, you also increase the pressure again, "thermal expansion". I would put a gauge somewhere on your water system and see what it reads, that would be a good starting point.
 

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Discussion Starter #10
Its electric and maybe 2 years old now. I put a post on here somewhere back when I had to install that because its wider than the old one was even though it is the same capacity. Some agency apparently up'd the insulation requirement for efficiency or something. It almost didn't fit between the framing but it did just barely fit. I never noticed the old valve in the old heater letting out water and it never leaked. It was 12 years old when it developed a leak in there somewhere so I had to replace it. I haven't noticed the new valve leaking at any time either. My water pressure is chronically on the low side but its tolerable. I think it was just a poorly manufactured valve in the new heater.

I actually considered going out to the scrap trailer and getting the old 12 year old one but with my luck it would have probably blown too. I may stiill go have a look at it and see what it looks like in there.
 
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