Decreasing Water Pressure

[Wpollock]

Facts:
1. Single story home built in 2019 with city water supply.
2. 60 psi pressure at nearest and farthest hose bibs from pressure regulator at move in.
3.Hot water tank has expansion tank.
4. Current pressure at same two bibs is 51 psi.
5. No leaks in any visible locations( city main meter box, owner's main shutoff valve box, pressure regulator box, all lawn irrigation valve control boxes, no running toilets, faucet leaks or pressure release valve, main water meter doesn't show any flow when all water outlets are in closed positions, no signs of any leak on sheetrock or floors.
No notification from city that there has been a pressure drop on main supply line for my area.
Is it possible that I simply need to adjust the incoming pressure back to the original 60 psi supply at the pressure regulator?
If so, how do I adjust the pressure on the hot water tank expansion tank to have the same pressure if needed?
Thanks for any thoughts.

 

[Reach4]

I applaud your rigor.

Do you have a way to read the pressure before the PRV? If not, I would consider asking the water department what to expect as the lowest incoming pressure, and if there have been changes.

To adjust the air precharge pressure of the thermal expansion tank, the water pressure should be near zero.

 

[Sponsor]

 

[WorthFlorida]

If so, how do I adjust the pressure on the hot water tank expansion tank to have the same pressure if needed?
Thanks for any thoughts.

With the water off to the expansion tank or WH, and if possible disconnect the tank to allow it to drain. Then pressurize it to 60 psi. Expansion tank should equal the average pressure, usually during the daytime.
The PRV only reduces pressure, not maintain 50 psi if the supply side pressure drops below 50 psi.

My home it's 70 psi. Over night it would go to 125 psi. Now it's about 90 psi with the expansion tank.

 

[Wpollock]

Service provider says main line pressure supplying service to homes on my street averages between 76 psi to 85 psi.
Interestingly, my daughter lives next door in an identical floor plan home built at the same time by the same builder. Her current pressure reading is 65 psi at both hose bids in the same locations as are mine. Is it a fact that when a PRV starts to fail and there are no detectable leaks, the most common scenario is an increase in the whole house pressure and not a reduction in pressure?

 

[Jeff H Young]

your pressure coming into the house and daughters should be identical other than a differential due to elevation . 15 psi differance between your home and your daughters provided that your home isnt 30 ft higher in elevation means to me that your regulators arent adjusted or functioning identically you should be able to get 65 psi as well . adjustment , servicing or replacing regulator is needed

 

[Wpollock]

Actually my daughter's home is about 6 ft higher than mine. I rechecked pressures at both of my bibs and get between a 32 to 33 psi reading at both with no water being used at the time of reading. Clearly there has been a significant drop ( around 30 psi ) since move in at my house. Now the question is: is the drop due to an issue with the service water meter or the PRV?

 

[WorthFlorida]

Rebuilt kits for PRV's are usually available so having to cut pipe would not be needed.

 

[Jeff H Young]

Actually my daughter's home is about 6 ft higher than mine. I rechecked pressures at both of my bibs and get between a 32 to 33 psi reading at both with no water being used at the time of reading. Clearly there has been a significant drop ( around 30 psi ) since move in at my house. Now the question is: is the drop due to an issue with the service water meter or the PRV?

if you arent using water and pressure only goes to 32 and there is 65 or 70 coming in it has to be the regulator