My water pressure is 100 psi inside just by the regulator. Yet all my garden hose bibs outside are at 40 psi. What is dropping this pressure? I want to use a hose end sprayer on my fruit trees but there isn't enough pressure to get a decent venturi effect. It sucks. Well, actually it DOESN'T SUCK!!
GWE
Is that static pressure (read on a pressure gauge connected to the bib with no water flow) or a dynamic pressure (read on the gauge while water is flowing from that bib or circuit)?
Static. In other words, a flow restricting hose bib *shouldn't* affect the pressure. And it's constant at all of my hose bibs. Weird. It's as though there's another regulator somewhere I don't know about.
Grant
Is "just by the regulator" a 'downstream location? What does the pressure measure at other points in the house?
Ken.
It's inboard of the regulator, if that's what you mean. The pressure tester I'm using threads onto a hose bib, and I don't have more of those around my house.
In point of fact, this discussion is now moot since I returned the nonfunctional sprayer and bought a better one. It works just dandy on
40 psi.Grant
You've got me curious as to why the pressure drop, though. Would an anti-backflow valve cause such a decrease?
Jon
I suspect you went from 3/4" copper to 1/2" on the others. Resistance to flow causes pressure drop. Ohms law for water.
Martin
Not for static pressure. When the system is static, the pressure is equal throughout the system (assuming all points are at equal elevation), even if the pipe was reduced to a capillary tube. Voltage law for water.
- Michael
Flow equals zero, therefore pressure drop due to resistance is zero.
I'm all over Ohm, Kirchoff, you betcha.
GWE
But are you measuring static pressure both times? Or are you running a hose and measuring the pressure with flow?
If it's static both times, then FIIK!
Did you rule out some gross difference in the gauges Grant? I couldn't tell specifically, but thought maybe you were telling us you had a permanantly mounted gauge inside the house and a different "hose bib" one you were using outside.
What say?
You can't leave us hanging in the dark without resolving what sounds like an "impossible" condition.
Jeff
Same gauge -- I measured it inside by the regulator, disconnected it (it just threads on like a hose nozzle) and carried it around and tested several of my outdoor hose bibs.
GWE
As mentioned above - this seems to be an impossible condition. Only two reasons for the difference in measured pressure come to mind. !. Your first reading "by the regulator" is actually on the supply-side of the regulator.
Ken.
Number three might be a small leak in the feed just outside the home. At least that would be the reason I'm accustomed to finding in problem pneumatic systems in machinery.
dennis in nca
A leak could cause a pressure drop, but it's highly unlikely. First, it would have to be downstream of the pressure regulator (thus probably inside the home). Second, it would have to be quite large to cause a 60 psi drop in pressure in the 1/2" pipes. Third, since the same pressure drop is measured at a number of hose bibs around the house, the leak would have to be in one of the major water supply "arteries" for the home. And for all those conditions to occur, it would probably be unlikely that the system would be able to maintain 100 psi anywhere downstream of the regulator. It would also be unlikely to go unnoticed by the homeowner.
- Michael
Wowza, I had to go to
I'll be remembering and probably using it myself, thanks.
Jeff
Just out of paranoia..... Your garden hose bibs aren't on 120 foot tall posts are they?
Mark Rand RTFM
No :-)
A plumber friend of mine says that counter to my understanding of flow reduction and pressure mechanics, it is the modern low-flow hose bibs that are to blame here. I don't understand how they work, but now that I have a sprayer that works and a hose bib under my house I can route a long hose from at 100 psi if I need it, I don't really feel the urgency any more.
GWE
. Been watching this thread for it's entirety and been kicking it around.
First stupid question: In your note above, Grant, you don't mention the "inside" pressure having been tested; whether it was upstream, or downstream.... from the regulator.... or "just inside". This leaves several doors open to question.
With static pressure the same throughout the system (where you can test t, i.e., the hose bibbs), common sense tells one that the hose bibbs are definitely downstream from "THE"........OR another regulator.
In some older homes, especially those plumbed for aftermarket soft water and/or R/O systems, installers will often run the upstream water supply directly to hose bibbs so as not to "waste" R/O, or soft water. (Thereby unloading Sodium laden compounds on site. Bad for plant life.) My point is, look or a secondary lateral that might just service those hosebibbs AFTER the regulator. It might well be where you least expect it..
Beyond that, your problem just does not equate...
bill
Oh, boy, this one was STUPID. The hose bib in my basement I measured was on the supply side of the regulator. My whole house was at 40 psi. When I cranked in the regulator a bit it came right up to 50 psi everywhere.
The world makes sense again.
GWE
Grant Erw> My water pressure is 100 psi inside just by the regulator. Yet all my
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