Water Pressure Regulator

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Topic Author
catchinup
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Water Pressure Regulator

Post by catchinup »

I was told by a plumber my water pressure incoming was at 100psi. I was in a work meeting and did not see the gauge readout. The plumber wanted to replace the regulator. I asked why can't it simply be adjusted vs replacement. He said better to replace.

Three years ago a plumber installed that regulator.. I'm pretty sure it was set at 60 PSI at the time.

If the PSI is high, is the plumber correct that it's better to replace it?

I think I can buy a gauge and just test it myself?
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southerndoc
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Re: Water Pressure Regulator

Post by southerndoc »

Sounds suspicious for a regular to go out in only 3 years.
random_walker_77
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Re: Water Pressure Regulator

Post by random_walker_77 »

Even with hard water, 3 years sounds short for a PRV to wear out. Personally, I'd get a water pressure gauge (about $12 at home depot) and see what the static pressure is. If it's off, there's a bolt on the top of the PRV that you can turn to adjust the pressure. When mine was off, I ended up needing to adjust it every couple of months until it maxed out, at which point it definitely needed to be replaced. Based on that experience, you might check on it and if you need to adjust it repeatedly, then proactively get quotes on a replacement.
twh
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Re: Water Pressure Regulator

Post by twh »

I had to replace mine recently.
As said, get a cheap gauge at HD or equivalent.
100 psi isn't good for anything in the house.
At 100 psi, if you have a hot water expansion tank, it may be ruptured as well and not working.
Many pressure reducing valves can be rebuilt with a kit from the manufacturer.
Many pressure reducing valves are installed with unions for easy replacement -- as long as you put in the same model. That's what I did.
PoorPlumber
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Re: Water Pressure Regulator

Post by PoorPlumber »

You can get a gauge that screws onto hose bibbs to check pressure provided they are tied in after the regulator. Most are.
Pressure will be the highest later in the evening.
PRV's are adjustable.
Due to small sized PRV's being inexpensive, most plumbers are reluctant to do much adjusting, rebuild, or clean any internal screens.
Labor doesn't pay out for the homeowner.
Liability doesn't pay out for the plumber.
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catchinup
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Re: Water Pressure Regulator

Post by catchinup »

Thanks for all the responses.

I purchased this test gauge at my local Home Depot.
https://www.homedepot.com/p/Watts-3-4-i ... /100175467

Around 15 minutes ago, attached it to a spigot in the rear of the house. Not sure it matters that I didn't attach it near the regulator in the front of the house? I can always test a second spigot if so.

The black needle is reading around 72 PSI. The red is around 90. I can leave it on overnight to see what happens.
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TnGuy
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Re: Water Pressure Regulator

Post by TnGuy »

When we first purchased our home the incoming pressure was 160 PSI (we live halfway down a hill that has a water tower not too far away). The pressure was so high (though we didn't realize at the time) that it blew out our dishwasher. I installed a PRV and set it at 60 PSI. It ended up that the PRVs lasted on average about 2 years, since the incoming pressure was so high.


David
"Money will not make you happy. And happy will not make you money." - Groucho Marx
random_walker_77
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Re: Water Pressure Regulator

Post by random_walker_77 »

catchinup wrote: Sun Jun 09, 2024 4:57 pm Thanks for all the responses.

I purchased this test gauge at my local Home Depot.
https://www.homedepot.com/p/Watts-3-4-i ... /100175467

Around 15 minutes ago, attached it to a spigot in the rear of the house. Not sure it matters that I didn't attach it near the regulator in the front of the house? I can always test a second spigot if so.

The black needle is reading around 72 PSI. The red is around 90. I can leave it on overnight to see what happens.
Sounds like you're fine then. If the water isn't running, the pressure should be the same everywhere, at the same height. Expect the pressure to drop a little if there's a volume of water running. The pressure will drop if you go up to the 2nd floor (about 5psi per 10 feet, iirc). I've read that 50 psi is a good setpoint, and that you want to keep it between 30 and 80.
PoorPlumber
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Re: Water Pressure Regulator

Post by PoorPlumber »

catchinup wrote: Sun Jun 09, 2024 4:57 pm Thanks for all the responses.

I purchased this test gauge at my local Home Depot.
https://www.homedepot.com/p/Watts-3-4-i ... /100175467

Around 15 minutes ago, attached it to a spigot in the rear of the house. Not sure it matters that I didn't attach it near the regulator in the front of the house? I can always test a second spigot if so.

The black needle is reading around 72 PSI. The red is around 90. I can leave it on overnight to see what happens.
The red needle is the "bump needle". (Just what I call it.)
An analog recorder if you will.

The black needle is the live pressure.
So if pressure rises it should go around and bump the red needle to whatever the highest pressure is between readings.

So you want to set the red needle with the center brass dial a few pounds above the black needle then leave overnight.
ncook303
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Re: Water Pressure Regulator

Post by ncook303 »

You're fine at 72PSI. The regulator can be adjusted if you want it back to 60psi. Google is your friend.
twh
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Re: Water Pressure Regulator

Post by twh »

TnGuy wrote: Sun Jun 09, 2024 5:17 pm When we first purchased our home the incoming pressure was 160 PSI (we live halfway down a hill that has a water tower not too far away). The pressure was so high (though we didn't realize at the time) that it blew out our dishwasher. I installed a PRV and set it at 60 PSI. It ended up that the PRVs lasted on average about 2 years, since the incoming pressure was so high.

David
Your situation is where you need to put in two PRV's in series...the first one knocks it down part way and the second knocks it down to the working level. This isn't all that uncommon a setup.
Topic Author
catchinup
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Re: Water Pressure Regulator

Post by catchinup »

So this morning the static black needle on pressure gauge was still at 72 and the red needle was around 90. If I were to adjust the regulator down to 60 PSI static I am not sure if that means that the spike pressure would also reduce?
twh
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Re: Water Pressure Regulator

Post by twh »

catchinup wrote: Mon Jun 10, 2024 10:23 am So this morning the static black needle on pressure gauge was still at 72 and the red needle was around 90. If I were to adjust the regulator down to 60 PSI static I am not sure if that means that the spike pressure would also reduce?
If the pressure is getting up to 90 psi and it is set for 60, I would say the PRV isn't working right anymore.
hoofaman
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Re: Water Pressure Regulator

Post by hoofaman »

We had a PRV (Pressure Regulator Valve) fail, and in our case water pressure would slowly rise to street pressure which was about 100 PSI overtime. You could see this with a pressure gauge, but it would take about 10 minutes after using water, and even a slightly dripping faucet would mask the issue

We have a phyn device which monitors pressure and initially alerted me, then I left a mechanical gauge on the hose which was slightly more downstream but matched the phyn measurements pretty closely

In our case, the plumber thought the reason our PRV valve failed prematurely was because we didn't have an expansion tank (we have a tankless water heater), I guess this could have caused added ware on the PRV, we replaced PRV and added expansion tank and haven't had any issues since
Last edited by hoofaman on Mon Jun 10, 2024 11:12 am, edited 1 time in total.
PoorPlumber
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Re: Water Pressure Regulator

Post by PoorPlumber »

catchinup wrote: Mon Jun 10, 2024 10:23 am So this morning the static black needle on pressure gauge was still at 72 and the red needle was around 90. If I were to adjust the regulator down to 60 PSI static I am not sure if that means that the spike pressure would also reduce?
Did you set it as I instructed earlier?
twh
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Re: Water Pressure Regulator

Post by twh »

hoofaman wrote: Mon Jun 10, 2024 11:04 am We had a PRV (Pressure Regulator Valve) fail, and in our case water pressure would slowly rise to street pressure which was about 100 PSI overtime. You could see this with a pressure gauge, but it would take about 10 minutes after using water, and even a slightly dripping faucet would mask the issue

We have a phyn device which monitors pressure and initially alerted me, then I left a mechanical gauge on the hose which was slightly more downstream but matched the phyn measurements pretty closely

In our case, the plumber thought the reason our PRV valve failed prematurely was because we didn't have an expansion tank (we have a tankless water heater), I guess this could have caused added ware on the PRV, we replaced PRV and added expansion tank and haven't had any issues since
If there is an expansion tank, it is probably set around 60 psi. A non-functioning PRV that lets the pressure get to 90 psi isn't the best for the life of the expansion tank either.
Topic Author
catchinup
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Re: Water Pressure Regulator

Post by catchinup »

PoorPlumber wrote: Mon Jun 10, 2024 11:12 am
catchinup wrote: Mon Jun 10, 2024 10:23 am So this morning the static black needle on pressure gauge was still at 72 and the red needle was around 90. If I were to adjust the regulator down to 60 PSI static I am not sure if that means that the spike pressure would also reduce?
Did you set it as I instructed earlier?
Yes, I did thanks!
Topic Author
catchinup
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Re: Water Pressure Regulator

Post by catchinup »

twh wrote: Mon Jun 10, 2024 11:16 am
hoofaman wrote: Mon Jun 10, 2024 11:04 am We had a PRV (Pressure Regulator Valve) fail, and in our case water pressure would slowly rise to street pressure which was about 100 PSI overtime. You could see this with a pressure gauge, but it would take about 10 minutes after using water, and even a slightly dripping faucet would mask the issue

We have a phyn device which monitors pressure and initially alerted me, then I left a mechanical gauge on the hose which was slightly more downstream but matched the phyn measurements pretty closely

In our case, the plumber thought the reason our PRV valve failed prematurely was because we didn't have an expansion tank (we have a tankless water heater), I guess this could have caused added ware on the PRV, we replaced PRV and added expansion tank and haven't had any issues since
If there is an expansion tank, it is probably set around 60 psi. A non-functioning PRV that lets the pressure get to 90 psi isn't the best for the life of the expansion tank either.
There is no expansion tank, actually. I have a tankless gas water heater inside the house. Is an expansion tank needed in that case?
PoorPlumber
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Re: Water Pressure Regulator

Post by PoorPlumber »

catchinup wrote: Mon Jun 10, 2024 12:17 pm
PoorPlumber wrote: Mon Jun 10, 2024 11:12 am
catchinup wrote: Mon Jun 10, 2024 10:23 am So this morning the static black needle on pressure gauge was still at 72 and the red needle was around 90. If I were to adjust the regulator down to 60 PSI static I am not sure if that means that the spike pressure would also reduce?
Did you set it as I instructed earlier?
Yes, I did thanks!
Then this confirms the regulator is allowing "creep" past setpoint.
Water heater could also be contributing depending on arrangement.
Recommended Opinion:
Replace PRV.
Put in expansion tank and set to PRV pressure.
Topic Author
catchinup
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Re: Water Pressure Regulator

Post by catchinup »

PoorPlumber wrote: Mon Jun 10, 2024 12:23 pm
catchinup wrote: Mon Jun 10, 2024 12:17 pm
PoorPlumber wrote: Mon Jun 10, 2024 11:12 am
catchinup wrote: Mon Jun 10, 2024 10:23 am So this morning the static black needle on pressure gauge was still at 72 and the red needle was around 90. If I were to adjust the regulator down to 60 PSI static I am not sure if that means that the spike pressure would also reduce?
Did you set it as I instructed earlier?
Yes, I did thanks!
Then this confirms the regulator is allowing "creep" past setpoint.
Water heater could also be contributing depending on arrangement.
Recommended Opinion:
Replace PRV.
Put in expansion tank and set to PRV pressure.
Thanks for the advice.
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CalPoppy
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Re: Water Pressure Regulator

Post by CalPoppy »

catchinup wrote: Thu Jun 13, 2024 10:30 pm
PoorPlumber wrote: Mon Jun 10, 2024 12:23 pm
catchinup wrote: Mon Jun 10, 2024 12:17 pm
PoorPlumber wrote: Mon Jun 10, 2024 11:12 am
catchinup wrote: Mon Jun 10, 2024 10:23 am So this morning the static black needle on pressure gauge was still at 72 and the red needle was around 90. If I were to adjust the regulator down to 60 PSI static I am not sure if that means that the spike pressure would also reduce?
Did you set it as I instructed earlier?
Yes, I did thanks!
Then this confirms the regulator is allowing "creep" past setpoint.
Water heater could also be contributing depending on arrangement.
Recommended Opinion:
Replace PRV.
Put in expansion tank and set to PRV pressure.
Thanks for the advice.
Adding an expansion tank fixed our issue. Our pressure was fine unless we ran hot water then closed all faucets, etc. Given hot water expands, the hot water in the pipes caused the pressure to spike.

On a related note, this issue surfaced after we installed a smart auto shutoff/monitoring device (ours is made by Phyn). First, Phyn detected several very small leaks that we fixed. That made the plumbing system tight, and therefore hot water in the system would cause the pressure to build. Turns out even a dripping faucet is enough to prevent the pressure to build.
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WoodSpinner
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Re: Water Pressure Regulator

Post by WoodSpinner »

catchinup wrote: Sun Jun 09, 2024 4:57 pm Thanks for all the responses.

I purchased this test gauge at my local Home Depot.
https://www.homedepot.com/p/Watts-3-4-i ... /100175467

Around 15 minutes ago, attached it to a spigot in the rear of the house. Not sure it matters that I didn't attach it near the regulator in the front of the house? I can always test a second spigot if so.

The black needle is reading around 72 PSI. The red is around 90. I can leave it on overnight to see what happens.
Just finished battling this issue ….

What confused us ll was the Water company changes the pressure at different (and somewhat random) times of the day. We did replace my regulator (hard water area) after about 8 years. It solved the issue (caused intermittent pinging in a Tankless Water Heater) and has stabilized pressure when measured at multiple times of the day over a week.

FWIW, our highest pressures seem to occur in the morning (at least in the winter when we were testing.

WoodSpinner
WoodSpinner
Topic Author
catchinup
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Re: Water Pressure Regulator

Post by catchinup »

CalPoppy wrote: Fri Jun 14, 2024 12:41 am
catchinup wrote: Thu Jun 13, 2024 10:30 pm
PoorPlumber wrote: Mon Jun 10, 2024 12:23 pm
catchinup wrote: Mon Jun 10, 2024 12:17 pm
PoorPlumber wrote: Mon Jun 10, 2024 11:12 am
Did you set it as I instructed earlier?
Yes, I did thanks!
Then this confirms the regulator is allowing "creep" past setpoint.
Water heater could also be contributing depending on arrangement.
Recommended Opinion:
Replace PRV.
Put in expansion tank and set to PRV pressure.
Thanks for the advice.
Adding an expansion tank fixed our issue. Our pressure was fine unless we ran hot water then closed all faucets, etc. Given hot water expands, the hot water in the pipes caused the pressure to spike.

On a related note, this issue surfaced after we installed a smart auto shutoff/monitoring device (ours is made by Phyn). First, Phyn detected several very small leaks that we fixed. That made the plumbing system tight, and therefore hot water in the system would cause the pressure to build. Turns out even a dripping faucet is enough to prevent the pressure to build.
PoorPlumber suggested an expansion tank for my home. Assuming it should be located near my indoor tankless water heater, I don't have a discrete place to put it.
bombcar
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Re: Water Pressure Regulator

Post by bombcar »

Amusingly enough the regulator may be causing the need for the expansion tank, because if water can't "push back" on the city supply lines, it has to get more pressure.

It should be able to go basically anywhere that the pipes reach.
trinc
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Re: Water Pressure Regulator

Post by trinc »

bombcar wrote: Fri Jun 14, 2024 4:55 pm Amusingly enough the regulator may be causing the need for the expansion tank, because if water can't "push back" on the city supply lines, it has to get more pressure.

It should be able to go basically anywhere that the pipes reach.
Adding a PRV creates a 'closed' system which requires an expansion tank.

Tim
RetiredAL
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Re: Water Pressure Regulator

Post by RetiredAL »

trinc wrote: Fri Jun 14, 2024 6:13 pm
bombcar wrote: Fri Jun 14, 2024 4:55 pm Amusingly enough the regulator may be causing the need for the expansion tank, because if water can't "push back" on the city supply lines, it has to get more pressure.

It should be able to go basically anywhere after the PRV that the pipes reach.
Adding a PRV creates a 'closed' system which requires an expansion tank.

Tim
"after the PRV" added by me. It is normally on a cold line, but that can be on a hot line.

The other important function that an expansion tank does it that is minimizes/eliminates the slamming of the PRV shut when water flow at a faucet is quickly turned off. Slamming shortens the life of the PRV.
Topic Author
catchinup
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Re: Water Pressure Regulator

Post by catchinup »

bombcar wrote: Fri Jun 14, 2024 4:55 pm Amusingly enough the regulator may be causing the need for the expansion tank, because if water can't "push back" on the city supply lines, it has to get more pressure.

It should be able to go basically anywhere that the pipes reach.
I find this whole topic interesting because when I purchased the home in 2009, the incoming pipes were all the original galvanized pipes which I didn't finish replacing entirely until 2020, nor did the house have a regulator until 2020. So I'm wondering how those old, badly corroded pipes were able to withstand the pressure. The regulator was installed after all plumbing had been replaced with copper and PEX, and the tank water heater was replaced with the tankless heater. Perhaps the tank water heater provided space for expansion?

Another curiosity is why the plumber who installed the regulator didn't suggest and expansion tank.
bombcar
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Re: Water Pressure Regulator

Post by bombcar »

Tanked water heaters and/or no PRV will handle it. Pressure gets "pushed" back up the pipe if you will to the city.

Even a corroded galvanized pipe can take a lot of pressure.
RetiredAL
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Re: Water Pressure Regulator

Post by RetiredAL »

High pressure will seldomly cause piping leaks. Pipes are incredibly strong, even when corroded.The first thing one sees with high pressure is a tendency for valve washers/disks have short lives. High pressure can cause a water heater to rupture sooner, but by days or weeks, not years.
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vnatale
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Re: Water Pressure Regulator

Post by vnatale »

This is all news to me. Do I have a Water Pressure Regulator in my house?
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twh
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Re: Water Pressure Regulator

Post by twh »

Google "water pressure reducing valve" and click on the images tab. If you have something that looks like this near the main water shutoff, then you have a PRV.

You typically don't need an hot water located expansion tank if the water expansion cause by the hot water heating up water is able to be "pushed" back to the city supply. That is, as you house water heater heats up new water, that pressure can by sent back into the city side. This won't be possible if you have a backflow preventer on your water line and I don't think most or all PRVs.

If the PRV is bad, then weird things can happen. You can have wild swings in pressure, so maybe your shower goes hot or cold when someone flushes the toilet. You can damage water valves such as in the icemaker or washing machine with high pressures. The high pressures might cause some flexible supply lines to leak or washer hoses to leak or worse. The high pressures will probably not affect the hard lines in the plumbing.

The high pressures can rupture the expansion tank if there is one - it has a diaphragm inside.

If you don't have an expansion tank and you need one, this can many times be seen as dribble from the hot water heater relief valve tube. This is because the water is getting heated up and the added pressure of the new hot water has no where to go and it minutely opens the hot water heater relief valve. This is also creating unnecessary stress on the hot water heater.
Topic Author
catchinup
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Re: Water Pressure Regulator

Post by catchinup »

bombcar wrote: Wed Jun 19, 2024 6:38 pm Tanked water heaters and/or no PRV will handle it. Pressure gets "pushed" back up the pipe if you will to the city.

Even a corroded galvanized pipe can take a lot of pressure.
So if you have a tanked water heater you don't need a regulator or expansion tank, even if city water pressure is 100 psi?
twh
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Re: Water Pressure Regulator

Post by twh »

catchinup wrote: Thu Jun 20, 2024 12:13 am
bombcar wrote: Wed Jun 19, 2024 6:38 pm Tanked water heaters and/or no PRV will handle it. Pressure gets "pushed" back up the pipe if you will to the city.

Even a corroded galvanized pipe can take a lot of pressure.
So if you have a tanked water heater you don't need a regulator or expansion tank, even if city water pressure is 100 psi?
There may be cases where you are totally fine with 100 psi, but that isn't going to be a normal condition for a house. 100 psi is a problem for all the fixtures and valves.

Technically, if you have a tank water heater and you have 100 psi city water and you are fine with 100 psi and you don't have a backflow preventer on the main line to the city, you don't have to have a PRV nor an expansion tank.

But, you don't want 100 psi, so yes you need both.
sunsetting101
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Re: Water Pressure Regulator

Post by sunsetting101 »

A higher pressure will cause more erosion of the piping fitting when it hits an elbow (higher flowrate=more erosion). The flowrate is some function of sqrt(delta P). So lowering your operating pressure will reduce the flowrate which will reduce erosion when water flows through the metal elbow. If your piping is all plastic (no elbow fittings), then never mind.
It might be worth considering to lower your operating pressure to 30 psig.
LotsaGray
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Re: Water Pressure Regulator

Post by LotsaGray »

catchinup wrote: Mon Jun 10, 2024 12:17 pm
PoorPlumber wrote: Mon Jun 10, 2024 11:12 am
catchinup wrote: Mon Jun 10, 2024 10:23 am So this morning the static black needle on pressure gauge was still at 72 and the red needle was around 90. If I were to adjust the regulator down to 60 PSI static I am not sure if that means that the spike pressure would also reduce?
Did you set it as I instructed earlier?
Yes, I did thanks!
Then you have a problem. Overnight the pressure reached 90#. Imo 72# was little too high but 90# is definitely too high. Anything over about 65#, imo, is getting too high and will stress your components in the house.

Even if it was only a spike, repeated spikes to 90# will cause damage. In some ways are spikes cause more damage than continuous high pressure.
NYCaviator
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Re: Water Pressure Regulator

Post by NYCaviator »

They are pretty cheap to replace and our plumber said they have a limited lifespan. You definitely don't want pressure at 90 or 100, even if they are spikes. I'd just get it changed and make sure they put in a good quality PRV. Or get a second opinion from another plumber.
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catchinup
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Re: Water Pressure Regulator

Post by catchinup »

What's a quality PRV to use? The one I have is Watts LF55BM1-XL.
twh
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Re: Water Pressure Regulator

Post by twh »

That's a fine model. You can get a repair kit:
https://www.watts.com/products/plumbing ... /lfn55b-m1
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catchinup
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Re: Water Pressure Regulator

Post by catchinup »

twh wrote: Fri Jun 21, 2024 3:26 pm That's a fine model. You can get a repair kit:
https://www.watts.com/products/plumbing ... /lfn55b-m1
Thanks
Topic Author
catchinup
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Re: Water Pressure Regulator

Post by catchinup »

NYCaviator wrote: Thu Jun 20, 2024 6:57 am They are pretty cheap to replace and our plumber said they have a limited lifespan. You definitely don't want pressure at 90 or 100, even if they are spikes. I'd just get it changed and make sure they put in a good quality PRV. Or get a second opinion from another plumber.
I'm confused. Based on feedback from others, the problem with the spiking is due to not having an expansion tank, not the PRV. Or is that incorrect?
twh
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Re: Water Pressure Regulator

Post by twh »

catchinup wrote: Mon Jun 24, 2024 11:07 pm
NYCaviator wrote: Thu Jun 20, 2024 6:57 am They are pretty cheap to replace and our plumber said they have a limited lifespan. You definitely don't want pressure at 90 or 100, even if they are spikes. I'd just get it changed and make sure they put in a good quality PRV. Or get a second opinion from another plumber.
I'm confused. Based on feedback from others, the problem with the spiking is due to not having an expansion tank, not the PRV. Or is that incorrect?
It is most likely the PRV responsible for the spiking.

But, depending on how your hot water plumbing is configured, it could also be affected by the lack of an expansion tank. For example, my plumbing has a check valve on the cold water line going into the hot water tank. That means that the expanding hot water cannot push back into the cold water side and would not cause your pressure gauge to see any higher pressures due to the hot water expansion. Now, I don't know if you have a check valve or not, it isn't required. If not, the hot water expansion can go back to the cold water side and that would cause your pressure gauge to see any higher pressures due to the hot water expansion. As an example, my expansion tank internal membrane was ruptured (i.e. not working) and the hot water expansion caused the hot water tank pressure relief valve to open slightly causing water to dribble out when the hot water was heating up. This pressure never got back to the cold water inlet because of the check valve that is installed.

You can test this by turning off the hot water for a day and monitoring the pressure with that gauge you have been using. Since the hot water heater is off, there will be no hot water expanding. If the pressure still goes up, it is for sure the PRV. If not, then could be the lack of an expansion tank.
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