I know that the pressure from the street is over 90psi in my area.
I have a pressure regulator (about 5 years old) on my main line and when all faucets are off and not drawing water the psi is set and maintains at 80psi. Plus I have an expansion tank on my main water heater and it is roughly 5 yrs old.
However, I notice that I have had very inconsistent water pressure at various times of the day. For example, today at 230p I saw 80psi on the meter then turned on an upstairs faucet and saw the meter drop to about 45psi with it open on full (and not coming out with a strong flow). Once I closed the faucet it returned to 80psi.
Similar experiment just now... started at 80PSI, turned on downstairs faucet1 right past the reduction valve and only dropped to 75, turned on the next faucet downstairs and dropped to 55psi.
I brought a plumber in who installed the reduction valve and he said that it was fine and this was a mystery.
I thought that setting the valve to 80PSI meant that it would maintain 80PSI under usage as long as the street was coming in higher than 80.
Does anyone have any ideas as to what the problem could be here? Does this sound like the reduction valve is going bad? Any suggestions would be greatly appreciated!