Water Heater leaks at very specific time of night

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Jeff H Young

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will be around stick with it ! this stuff isn't that complex. just a little more for you to understand when those PRV go bad they often allow pressure to creep up they will reduce the pressure still but when no water is used it internally leaks water pressure into house side very slowly allowing pressure to go high. Rebuilding a PRV can be worth it but very often is not I rebuilt mine that was only a few years old but a 10 or 20 year old and save 30 bucks not worth it but do your research.
To me its worth what you learn to DIY than to pay some guy that may or may not do it right plus next time you know what's going on.
Ill do stuff myself and not even save money not to have to deal some Bozo
 

nesappa

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will be around stick with it ! this stuff isnt that complex. just a little more for you to understand when those PRV go bad they often allow pressure to creep up they will reduce the pressure still but when no water is used it internally leaks water pressure into house side very slowly allowing pressure to go high. Rebuilding a PRV can be worth it but very often is not I rebuilt mine that was only a few years old but a 10 or 20 year old and save 30 bucks not worth it but do your reasearch.
To me its worth what you learn to DIY than to pay some guy that may or may not do it right plus next time you know whats going on.
Ill do stuff myself and not even save money not to have to deal some Bozo
Makes 100% sense. Agreed on the deal with some bozo part. Been there done that a few times. Thats life I guess.

Of note, places like this forum are a breath of fresh air and help restore peoples faith in humanity.
I know I go a little overboard but getting feedback from like-minded folks willing to help really is something extraordinary to me.
 
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jadnashua

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The more pressure drop the PRV needs to do, the quicker it's likely to start to leak and fail. Most have a maximum input pressure, and in worst case scenarios, you may need to reduce pressure in stages with two of them in series. The max input pressure should be in the specs of the PRV. It's the difference between inlet pressure and the adjusted outlet pressure.

Most municipal water supplies don't have a lot of grit in their water, but at least where I live, about once a year, they flush the lines by opening up a bunch of fire hydrants full bore, and the water for the next 10-hours or so tends to be brown with the crud that knocks off of the insides of the main line. That's usually small enough where it will flush through, but not necessarily. They usually announce when that's going to happen. You might want to create your own max flow situation after that to flush your lines internally after it clears up in the supply.

I live in a townhouse. The main water main to our complex is like a 6" diameter pipe. A couple of years ago, we needed to do some maintenance, and found that we couldn't fully close the shutoff/isolation valves. When the plumber inspected, we found that that fine silt had accumulated at the bottom of the pipe and over the years, since the valves had not been used, hardened into almost sedimentary rock...we had to cut out the pipe and install new.

It's not a bad idea to cycle any supply/shutoff valves on occasion to help ensure they'll work when you need them. That silt can accumulate in a PRV, too.

Where I grew up, prior to installing a PRV, the pressure from the utility was enough where it could knock a glass out of your hand when filling it at the sink if you weren't careful! Made washing the shampoo out of your hair easy, though. In a hilly area, the utility may need to supply a pretty high-pressure stream to get the water over the hills and to the customers sitting at the tops of those hills, and more to refill the water towers that tend to sit up high as well. Those at the bottom of the hill can then see some significant pressure.
 
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nesappa

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The more pressure drop the PRV needs to do, the quicker it's likely to start to leak and fail. Most have a maximum input pressure, and in worst case scenarios, you may need to reduce pressure in stages with two of them in series. The max input pressure should be in the specs of the PRV. It's the difference between inlet pressure and the adjusted outlet pressure.

Most municipal water supplies don't have a lot of grit in their water, but at least where I live, about once a year, they flush the lines by opening up a bunch of fire hydrants full bore, and the water for the next 10-hours or so tends to be brown with the crud that knocks off of the insides of the main line. That's usually small enough where it will flush through, but not necessarily. They usually announce when that's going to happen. You might want to create your own max flow situation after that to flush your lines internally after it clears up in the supply.

Where I grew up, prior to installing a PRV, the pressure from the utility was enough where it could knock a glass out of your hand when filling it at the sink if you weren't careful! In a hilly area, the utility may need to supply a pretty high-pressure stream to get the water over the hills and to the customers sitting at the tops of those hills, and more to refill the water towers that tend to sit up high as well. Those at the bottom of the hill can then see some significant pressure.
Im gonna research this and make a call to the water company per a prior suggestion. Makes sense I ll keep reading to find more sense out of it.

I read this like having two PRVs in series. Setting the first to a higher PSI maybe 90 then a second at say 70. Something along these lines.
Ive got research to do.

For reference we never see excess pressure at any faucet. But, my peak pressure is happening around 3AM so we would not likely experience it so to speak outside of the 1/4 - 1/2 gallon discharge we are seeing.

At the end of the day, the new t&P and ET did significantly reduce discharge as prior to this it was relatively constant. So if I have a faulty PRV it is doing something, just not enough.
 
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Jeff H Young

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I've never doubled up on PRV's here but seen mention in the manufactures paper work a lot of my area in So Cal has high pressure so I deal with lots of homes with PRV but not necessarily service or repair that many . but I'll tell you it isn't just a install and forget they can act up make strange noises etc but I'm guessing mainly around a life of 5 years or 10 if lucky but some problems go un noticed or ignored for many years you can usually get away with this negligence a long time.
 

Master Plumber Mark

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You should probably change the pressure relief valve too ,,,,,
because once it trips it can be just a little sloppy after that
The Wilkins PRV valve is a pretty good one to get.

also on another note, I cant see any support on that expansion tank

you should put a brick or some kind of wedge
under that thermal expansion tank that is just basically swinging in the wind.

the Sharkbites look ok -- for what they are --- but the weight of the tank just
hanging on a Sharkbite fitting is not good at all.....
PLEASE Cut something to size and tuck it under the tank down to the heater for
better support..........or some day you might regret it....
 

nesappa

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You should probably change the pressure relief valve too ,,,,,
because once it trips it can be just a little sloppy after that
The wilkins prv valve is a pretty good one to get.

also on another note, I cant see any support on that expansion tank

you should put a brick or some kind of wedge
under that thermal expansion tank that is just basically swinging in the wind.

the sharkbites look ok -- for what they are --- but the weight of the tank just
hanging on a sharkbite fitting is not good at all.....
PLEASE Cut something to size and tuck it under the tank down to the heater for
better support..........or some day you might regret it....
I will look into this and may likely install a bracket and move the ET to horizontal installation.

Thanks,
 

nesappa

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*Updated 01/24/2022.

I turned the water off at the main last night around 8PM. I left pressure in the lines and left the WH on.

No water discharge and no spike in PSI.
This likely confirms PSI spike is coming from the city water through a the faulty PRV.

I ll be looking to rebuild or replace the PRV.
I will also be turning the water main off every night until then to hopefully keep some wear and tear down on the new Expansion Tank bladder.

Thanks,
 

Jeff H Young

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*Updated 01/24/2022.

I turned the water off at the main last night around 8PM. I left pressure in the lines and left the WH on.

No water discharge and no spike in PSI.
This likely confirms PSI spike is coming from the city water through a the faulty PRV.

I ll be looking to rebuild or replace the PRV.
I will also be turning the water main off every night until then to hopefully keep some wear and tear down on the new Expansion Tank bladder.

Thanks,
nesspa, Yep you are on track.
 

nesappa

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*Update 01/26/2022:

I have purchased the following as this appears to be a direct replacement. Repair kits are not available at this time that I can find, but I will be checking regularly to hope to grab one up when available.


This has a by-pass check valve. As I am not familiar with this, does anyone know if this will cause me an issue during my known pressure spike from the city water?

Any further opinions welcome.

Thanks,
 

Reach4

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This has a by-pass check valve. As I am not familiar with this, does anyone know if this will cause me an issue during my known pressure spike from the city water?
Bypass means that if the inside pressure gets to be higher than incoming pipe pressure that the regulator passes water toward the incoming pipe. If you have no check valve on the meter or elsewhere, this could keep pressures down in the house, even if the thermal expansion tank went bad. The water company probably put a check valve at/in the meter, so the by pass feature won't affect things.

My first thought was that bypass and "check valve" were contradictory, but now I realize that the bypass is a check valve in parallel with the regulating valve, and points outward.

Note there is a separate screen on the input. If you ever notice increased pressure drop when you flow significant amounts, then clean the screen.
 
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nesappa

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Bypass means that if the inside pressure gets to be higher than incoming pipe pressure that the regulator passes water toward the incoming pipe. If you have no check valve on the meter or elsewhere, this could keep pressures down in the house, even if the thermal expansion tank went bad. The water company probably put a check valve at/in the meter, so the by pass feature won't affect things.

My first thought was that bypass and "check valve" were contradictory, but now I realize that the bypass is a check valve in parallel with the regulating valve, and points outward.

Note there is a separate screen on the input. If you ever notice increased pressure drop when you flow significant amounts, then clean the screen.
Heard Reach4.

Makes sense. I hope to wrap this thing up this weekend. I am going to work on installing the expansion tank horizontally with a bracket to for added security there also.
 

Reach4

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Makes sense. I hope to wrap this thing up this weekend. I am going to work on installing the expansion tank horizontally with a bracket to for added security there also.
I would leave the pressure tank where it is, and do as Mark suggested-- put a block between the tank and the top of the WH to take much of the weight. Wedges/shims can be handy for tuning height.
 
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Jeff H Young

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XTank orientation should be ok . Anything is possible but based on what I've seen and see in an area that's not backwards in water supply Id say you probably don't have a check valve in your water service from street to house I don't see them that much brand new subdivision maybe? and whether you have a check at meter or not you need a functioning PRV on a house with 150 psi coming in at night or above 80 psi at any time technically and if properly built
 

wwhitney

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FWIW, the OP's situation is a possible example of what a PRV with bypass is good for. If there's no upstream check valve, and if the municipal pressure is normally reasonable (e.g. 60 psi), and if there are only short duration spikes to higher pressure (say 150 psi every night from 3-4 a.m.), and if you're confident that there will be no significant thermal expansion during that period (could be assured with a water heater timer, e.g.), then a PRV with bypass could be used in lieu of an expansion tank.

In practice, that seems like too many ifs, so the expansion tank is still a good idea.

Cheers, Wayne
 

Jeff H Young

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I may be incorrect but any time code requires a PRV I belive an x tank is required by code . perhaps even if the prv isnt" required "but one is is installed it may require the tank Ill have to reasearch again
 

wwhitney

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Good point about the code requirements, in the UPC it's in 608.2:


So my earlier comments are restricted to the physics, but the expansion tank is still required by code.

Cheers, Wayne
 

Reach4

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So my earlier comments are restricted to the physics, but the expansion tank is still required by code.

Cheers, Wayne
California? Sure. In Chattanooga or nearby? I suspect there is not such a requirement, but I don't have a cite.
 
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