Recurring whole house low water flow

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fatima526
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Recurring whole house low water flow

Post by fatima526 »

My house has a pressure reducing valve (PRV) as the first thing in-line from the water supply line coming into the basement.

I’ve had the PRV replaced 2 times in the last few years. Each time, the symptom was reduced flow from all faucets. Also, the washing machine would take a long time to fill, same with toilet after flush. The oscillating lawn sprinkler water would come out only about 10 inches high, and not even enough flow for it to oscillate.

I used different plumbers (both reputable) for each of the 2 recent low pressure issues. Both advised the pressure coming in from the street into the house was very strong / not the issue. Each of them replaced the PRV and the issue seemed to resolve for 12 months (first replacement) and 18 months (2nd, most recent replacement).

I measure the PSI after the most recent replacement, and was 60 PSI at both the outdoor faucet and at the slop sink in the basement. Now, the issue has returned, and both those locations measure 40 PSI.

None of my neighbors have low pressure issue.

There’s no evidence of leaks or increased water consumption. I am the only person in the house.

I do believe each plumber went to the same local plumbing supply house to procure the replacement PRV.

It’s possible that is just incredibly bad luck to have 2 PRVs fail in such a short period. But before I have a plumber in to do what is likely another PRV replacement, is there any other thing to consider / have the plumber check?

Thanks for any guidance!
BrklynMike
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Re: Recurring whole house low water flow

Post by BrklynMike »

I'm having the exact same problem but I have a well. Meter says 60 psi but the flow is terrible and seems to be influenced if it runs all hot or all cold. Would love to hear from other people on this issue because it drives me nuts.
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snackdog
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Re: Recurring whole house low water flow

Post by snackdog »

Check for any large leaks inside or outside?
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linuxizer
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Re: Recurring whole house low water flow

Post by linuxizer »

Should last decades not months.

Look up model and download the manual. There’s only a few major brands and they all have manuals on website.

Make sure pressure is set right, if not do so.

Open it up and check for mineral deposits gumming it up.

Hire another plumber and buy the best/simplest part you can find. Have her plumb in a bypass with a ball valve in case this happens again.
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Sandtrap
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Re: Recurring whole house low water flow

Post by Sandtrap »

linuxizer wrote: Mon Oct 03, 2022 2:32 pm Should last decades not months.

Look up model and download the manual. There’s only a few major brands and they all have manuals on website.

Make sure pressure is set right, if not do so.

Open it up and check for mineral deposits gumming it up.

Hire another plumber and buy the best/simplest part you can find. Have her plumb in a bypass with a ball valve in case this happens again.
+1
This is not a complex issue.
And the existing system setup, and PRV, if done well, should be trouble free for many many many years.

Excellent point on the bypass loop with a ball valve.

To OP:
What is the incoming street water pressure to the unit in PSI????

Before the Pressure regulator: IE: 110 PSI???, 90 PSI??? etc.

j :D
Last edited by Sandtrap on Mon Oct 03, 2022 7:08 pm, edited 1 time in total.
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RetiredAL
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Re: Recurring whole house low water flow

Post by RetiredAL »

Sandtrap wrote: Mon Oct 03, 2022 3:34 pm
What is the incoming street water pressure to the unit in PSI????

j :D
Does it stay low (40psi) all the time, or does it come back up?

We used to live in a house where the area's tower water tank would often run out due to late afternoon/evening watering demand, so the main pressure was only what the well pump could provide at that flow rate, around 30 psi. Solution: The City added another well and tank. After that, no pressure problems.
Topic Author
fatima526
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Re: Recurring whole house low water flow

Post by fatima526 »

linuxizer wrote: Mon Oct 03, 2022 2:32 pm Have her plumb in a bypass with a ball valve in case this happens again.
Thanks for your response!

I will check the manual. I am leery of adjusting the pressure on my own, however. My understanding is too high a pressure can cause leaks. There is no PSI meter on the PRV, so have to make an adjustment , then go over to the slop sink and measure the resulting PSI it from there.


Not sure the purpose of the bypass with ball valve .. will you please share more on that?
Silverado
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Re: Recurring whole house low water flow

Post by Silverado »

How are you measuring the pressure at the outdoor faucet and slop sink?

When the pressure was at 60 psi after replacement was the flow fine? And for a decent duration?
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fatima526
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Re: Recurring whole house low water flow

Post by fatima526 »

Sandtrap wrote: Mon Oct 03, 2022 3:34 pm
To OP:
What is the incoming street water pressure to the unit in PSI????

Before the Pressure regulator: IE: 110 PSI???, 90 PSI??? etc.

j :D
I don't know the exact PSI coming in from the street. There is no meter there. Although both plumbers indicated very healthy street pressure in the course of the recent PRV replacements, I believe the 110 PSI number was mentioned the most recent replacement.
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Sandtrap
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Re: Recurring whole house low water flow

Post by Sandtrap »

fatima526 wrote: Tue Oct 04, 2022 7:26 am
Sandtrap wrote: Mon Oct 03, 2022 3:34 pm
To OP:
What is the incoming street water pressure to the unit in PSI????

Before the Pressure regulator: IE: 110 PSI???, 90 PSI??? etc.

j :D
I don't know the exact PSI coming in from the street. There is no meter there. Although both plumbers indicated very healthy street pressure in the course of the recent PRV replacements, I believe the 110 PSI number was mentioned the most recent replacement.
To OP:
Ok
That sounds about right for many city streets with fire hydrants and variable topography. The pressure is that high to feed the fire hydrants (volume and pressure), then is reduced for each home because 110, etc, would prematurely wear out valve seals, and cause other issues over time. Although, curiously, there are many instances where homes and buildings with this pressure exist with not too many more issues than in the 50-70 psi range. This was told to me by a retired city fire inspector and also several long time plumbing contractors in the city.

To OP:
So, given you have enough pressure, the next chain of diagnosis is from that point of 110 PSI then into your home from the main feed and in.

I hope this is helpful
j
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Topic Author
fatima526
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Re: Recurring whole house low water flow

Post by fatima526 »

Silverado wrote: Tue Oct 04, 2022 7:22 am How are you measuring the pressure at the outdoor faucet and slop sink?

When the pressure was at 60 psi after replacement was the flow fine? And for a decent duration?
A simple meter that screws on the faucet.

Yeah the flow is good when the pressure measures 60 PSI. At 60 PSI the oscillating sprinkler works as expected, wash machine fills as expected, etc.

As to duration, the PRV was last replaced May 2021, and flow had been good from that point until this past week ( late Sep 2022).
valleyrock
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Re: Recurring whole house low water flow

Post by valleyrock »

+1 Bypass helps diagnose the problem.

+1 RTFM . Could be default setting on new PRVs is low.

You could still ask the city to verify that their side is ok
senex
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Re: Recurring whole house low water flow

Post by senex »

OP, I recently had a similar experience with reduced flow.

Most PRVs have a fine mesh filter at their input. When the filter clogs, it causes substantial pressure reduction when water is flowing. For instance, whether clogged or not, I read 50psi when all faucets are off; but when I'm pulling 8gpm, it's 40psi if clean, 20psi if clogged.

Many cities have particulates in the water supply -- calcium, limestone, etc. They get trapped in the mesh. It's particularly bad if your water supply has turned off recently; when the main pipes lose pressure, it shakes loose extra particles.

My PRV is mechnically simple. You can completely disassemble it with a wrench & screwdriver, and it's obvious where gunk has accumulated. After cleaning mine out, my pressure returned to normal and the PRV worked as if new. My PRV is installed on its own section of pipe with screw-off couplings so it can be removed, cleaned, & replaced with just a wrench, no soldering etc.

Good luck.
Topic Author
fatima526
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Re: Recurring whole house low water flow

Post by fatima526 »

Thanks everyone for your responses. I am going to check the manual and see if I can do any thing more on my own before calling the pros.

Regards,
ncbill
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Re: Recurring whole house low water flow

Post by ncbill »

senex wrote: Tue Oct 04, 2022 11:01 am OP, I recently had a similar experience with reduced flow.

Most PRVs have a fine mesh filter at their input. When the filter clogs, it causes substantial pressure reduction when water is flowing. For instance, whether clogged or not, I read 50psi when all faucets are off; but when I'm pulling 8gpm, it's 40psi if clean, 20psi if clogged.

Many cities have particulates in the water supply -- calcium, limestone, etc. They get trapped in the mesh. It's particularly bad if your water supply has turned off recently; when the main pipes lose pressure, it shakes loose extra particles.

My PRV is mechnically simple. You can completely disassemble it with a wrench & screwdriver, and it's obvious where gunk has accumulated. After cleaning mine out, my pressure returned to normal and the PRV worked as if new. My PRV is installed on its own section of pipe with screw-off couplings so it can be removed, cleaned, & replaced with just a wrench, no soldering etc.

Good luck.
There could also be a separate sediment filter.

I had a relative who moved into a home and then noticed low water pressure.

Turned out the previous owner was too cheap to replace the sediment filter.
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Re: Recurring whole house low water flow

Post by Ron »

We had a problem with our water pressure years ago. Had the city check their line and found no problem. They were the ones that suggested we have our soft water conditioner checked. Found out that was the problem. A small piece of plastic from a solar salt bag fell off during a refill clogged the works :annoyed ...

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onourway
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Re: Recurring whole house low water flow

Post by onourway »

I agree that it's most likely something clogging that valve. Our city has text/email alerts you can sign up for that include notices when work is being done on things like water mains, streets, etc. When neighbors start complaining about brown water or low pressure, I can point them at these notices. If you could get such information, you'll know when to watch out for this issue in the future.
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