Is there any way to distinguish between the two problems? failed PRV/blocked wirsbo PEX fitting
There is 80 PSI static pressure at the rear hose bib but when
you turn on the kitchen faucet the pressure dropped to 45 PSI.
There is not enough water pressure for two fixtures to work with good volume at the
same time yet each individual fixture works on it's own.

My thoughts are that there is a failed PRV because front hose bib
reads near 84 PSI 4 pounds over max by code. This house was professionally
plumbed near 10 years ago. Besides digging up the front yard and looking
for a PRV I looked everwhere else did not find one. BUT keep in mind that this guy
cut into the main 1" PVC and although I'm careful about rocks and dirt
it is possible something got into the line...

What symptoms in the water system are unique to failed PRV and what symptoms are
unique to restricted flow thru a fitting or valve?
And if I do have something lodged in a fitting what steps would be taken
to dislodge and remove the object?

thanks for any input on this.



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your symptoms are those of a resrtiction. BUT, you have to determine if there is a PRV. i would think that after 10 years the inlet filter screen on a PRV would be a prime suspect.
can you tell if the outside faucet comes from the house piping or could it come from before an alledged PRV?

Not sure if bypasses are mandated code but I always install them just for this reason. Would be an easy test if you had one.

outside the house foundation the original plumber transitioned from 1" PVC to 1" PEX than ran wild thru the crawl space and up into the garage wall. In the garage there is a 1" whole house ball valve shut off and after that is the first tee that feeds the hose bib off a separate wall. After the whole house shut off the water dives back in the wall where i'm thinking the plumber ran the PEX thru the wall to feed the WH and then went up into the attic space to run all the rest of the water. I found yesterday two 3/4 PEX lines lines coming up into the attic.

So after talking with a plumber friend of mine he suggested that perhaps I could try air or water to back flush the piping towards the meter. There is a union on the meter so I could easily disconnect at the meter then either try to build up to 100 PSI and then open the valve at the meter to release air and hopefully dislodge object OR borrow the neighbors hose to attach to the wash machine box to flush water back.

According to the homeowner he had zero pressure issues before I cut his mainline and worked on the repair. So I'm started to come around that there is no PRV just some debris line. Total bummer. Service plumbing is never boring but sometimes you can really get your butt kicked. PS. Spent an half hour chasing his precious kitty cat that decided to check out the crawl under the house and then got freaked out. yikes. Disaster except that now he has no huge leak in his yard. Heading back to work for free at some point to solve this. Thanks again for comments. Iron sharpens iron.



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We always test fixtures for Pressure issues before we do any work, ate too many jobs I know had Problems before we were there and as soon as you touch it....you own it. P.s...what ever happened with that old tub waste job Pipe runner?. Would love to see some pic's.

good advice NoHub. thank you. OK will do more investigation of water system before doing repairs from now on.
Never know what preexisting problems might be there is you don't look
Waste and overflow project never happened. I told her my supervisor suggested to
replace the tub and redo the underfloor plumbing. Never heard back.
Now onto my current problem. What steps would you take to try a backflush?
I'm going to redo the tie in to the meter as I added 4 90's, a 3/4 ball valve, adapters etc.
worried that my band aid fix is the culprit for the reduced house pressure. Then
if that doesn't help with the house pressure start checking system for blocked fitting/ buried
PRV?

@ Packy.....rocks at first PEX 90 inside home.
nice diagnostic from across the country.
thanks for sharing your expertise.

this plumber will be taping all open pipes shut
while there's an open ditch. some lessons are learned the hard way.