Water Pressure Range Question

[DerbyDad03]

This is more of a discussion starter than a real "I need an answer" question.

If you Google around, you'll find that many sites list "normal" residential water pressure as a range, mostly 40 - 60 PSI.

For example, this is typical:

"Water pressure in the District typically ranges from 45 - 125 psi; however, typical residential systems are designed to function best under a pressure of 40 - 60 psi. If the water pressure entering your home exceeds this level, you should install a pressure regulator in the line to reduce the pressure to an acceptable range.

Why say reduce it to a "range"? Why not say "Adjust the PRV to reading of 55 PSI" or "60 PSI".

Is there really no noticeable difference between 40 PSI and 60 PSI?

[Robert Neville]

There is for me. We're on a well with a storage tank located about 250' away and

100' below the house grade. A 5 stage booster pump set to output 65 psi at the tank level results in about 40 psi at the entrance to the first floor of the house, less after distribution throughout the first floor and even less on the second floor.

Would love to have 60psi at the house entrance, but that would involve replacing the booster pump with a very expensive 8 stage booster pump or installing a second booster at the house.

[Tony Hwang]

Hi, You can't regulate pressure to a specific number at all times. Our house pressure is fluctuating from 50 to 70 psi or so depending on what is going on in and around the house. Bathing, Laundry, sprinkler, etc. We have a afjustable pressue regulator.

[Ed Pawlowski]

Not a big difference. If they stated a particular setting, people would go nuts trying to achieve 50 psi and complain if it dropped to 48 psi or went up to 52 psi. Saves a lot of phone calls to the water department that way.

[The Daring Dufas]

Every Watts water pressure regulator I've installed was factory set to 50psi. I imagine water saving plumbing fixtures use 50psi as a standard for calculating water flow. If you want a bit more water out of your nanny state shower head, I suppose adjusting the water pressure higher could help. :-)

TDD

[Harry K]

Something does not compute. Psi of 65 should only be 22 psi at 100' rise...some less than that after the loss through 250' of pipe.

Harry K

[Steve Barker]

or drilling out that little plastic washer in there..... whoops, did i say that?

[The Daring Dufas]

When I've traveled, I have a shower head and tools in my luggage. Not air travel mind you but road travel for service calls and installations. I was usually able to change the shower head in a motel room to my pre- drilled unfettered shower head without much trouble. I don't like running around inside a shower trying to get wet from the little sprinkle. :-)

TDD

[DerbyDad03]

way.- Hide quoted text -

I seriously doubt that all of the various websites that state a "range" are concerned with limiting the phone calls to the water authorities.

In other words, I don't think that that is the *reason* they use a range instead of a hard number.

[DerbyDad03]

re: "You can't regulate pressure to a specific number at all times."

But I can regulate *static* pressure to a specific number, therefore if a specific number were stated for the maximum recommended pressure after the PRV, it would only go down from there when fixtures are in use (dynamic pressure) except for the occasional rise when water heater cycles, etc.

[Harry K]

And no flow=3Dno water being used so your point is? Static pressure is pretty immaterial in a water system.

Harry K

[DerbyDad03]

How can static pressure be immaterial if problems caused high static pressure is the reason PRV's are recommended if the street pressure is above 70 PSI?

[DerbyDad03]

Well, then you don't agree *100%*, now do you? ;-)

Except that 60 is 50% higher than 40, so that's quite a difference.

You mean like me? ;-)

[Ed Pawlowski]

In other words, I don't think that that is the *reason* they use a range instead of a hard number.

***************************************************************

You have a good point. The phone calls would be to the regulator company's tech support. "I set my regulator to 50# but it creeps up to 53#. Should I return it? "

There is NO reason to state a particular pressure because it is virtually impossible to hit consistently and is not needed. I run a shop with boilers, compressors, machinery, pumps, and more, and none give anything more than a range because that is the practical way things work. We have hundreds of regulators and gauges and they all vary under most conditions.

The Space Shuttle may have tighter numbers. Your blood pressure does not. Ask your doctor what normal heart rate is.

[Robert Neville]

60 psi is hardly stressing the plumbing. The booster pumps we use (Goulds Aquaboost IIs) are rated to output up to 100 PSI as are the water system service lines. And because we live in an area where power can go out for extended periods of time, we do keep a 50 gallon gravity feed tank of emergency water in the garage along with two 5 gallon jerry cans. Have used them more than once!

I hate low flow / low pressure showers and have been known to modify the showerheads accordingly.

[Harry K]

Yep. Normal recommedned range for residential is low of 40psi to high of 60. They figure anything above 60 is both not needed and does stress fittings.

Where pressure regulators are required they will usually be set around

1. Well systems witll be set cut on/off 40/60 or 30/50. I am at

30/50 and find that some impulse sprinklers do not operate well at the 30psi end. Too lazy to adjust it.

The booster pumps we use (Goulds

Heh! Just went through most of a day with power outage. Very high wind storm - even had gusts into hurricane range - started in the evening. I _knew_ the power would go out sometime so I went around and got out flashlights, candles, etc. Did I remember to draw some 5 gal buckets of water to at least flush toilets with? Nope. Had to run to town the next morning to even have water to make coffee with (wood stove).

Harry K

[Harry K]

t 250' away and

volve replacing

I assumed (I know) that that would be read as "after" a PRV is set up.

Harry K

[Harry K]

t 250' away and

volve replacing

quoted text -

??? Do you have a point that is unknown to everyone already? To make it clear. I know what a PRV vavle is and what it does.

BTW the PRV does reduce pressure even at static. Case in point was my town down in a canyon. They built a new reservoir up on the rim. Blew fittings all over town _even when no water was being used_. Also my mothers house when I installed the PRV there. Reduced pressure to

55 psi _static_.

I repeat - static pressure is pretty meaningless in the operation of a water system. It is what it does _dynamically_ that counts.

My original system here was from a commuity well over a 1/4 mile away. Static (30/50) was just fine, dynamic wouldn't run an impulse sprinkler.

Harry K

[Tony Miklos]

I don't think Stormin Mormon meant you are stressing the system, just that your system is complex, so it would be a good idea to have some extra water on hand. That's how I read it anyway.

[Robert Neville]

That's definitely true. I manage the water system for a 28 home mountain subdivision. It consist of 8 wells, storeage tanks and booster pumps. Most of the properties get a pretty good service, but we have a few that need some tweaking. Every year we put a notice in the newsletter that reminds people they need an emergency backup for water.