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All the plumbing in our 100 year old home has been replaced. The pressure coming in from the street is prefect as reflected in our stationary tubs. (The city came out and tested the pressure and checked for leaks - no issues there) But the rest of the house is weak. Why and How can we fix this? We have asked so many plumbers, heating contractors (we have radiators) and general handymen about this and they all suggest the same -"It must be the pressure from the street" It is not. So then what?

Re: Pressure

The pipes maybe, something like impeded flow due to sediment or deposits, changes from small diameter to larger diameter just before the faucets are the only things I could think of.

I'm not saying repipe your house but maybe something like that is going on.

Or a washer in some joint is causing a low flow.

Re: Pressure

Pressure from the street supply is one thing.

Flow (amount of water delivered in X amount of time) is another thing altogether.

(Even an 1/8" pipe can have super pressure, but can't deliver much water in a minute. If the street supply diameter is choked down from accumulation of lime, calcium, etc.....flow will be hampered/restricted.)

But the street supply might not be the problem at all.

Your tub faucets won't have any flow restrictors. Full flow there. But...newer shower heads and faucets, etc...all have flow restrictors to minimize consumption. (These can usually be easily removed.)

First things to check (and easiest) .......remove any and all aerators from all faucets and check for gunk in those screens. If you had the water shut down to replumb.... there's a good chance that particles dislodged and are now plugging the aerators, toilet refill valves, etc. (The tub valve valves probably won't have any screens or tiny orifices to become plugged.)

These particles can also impede the small holes in the flow restrictors of the shower head, etc. So if there are particles in the faucet aerators and the shower head flow is also restricted......try removing it and cleaning out any particles there.

Most toilet refills can be disassembled, cleaned and reassembled. If yours can't, you may have to replace it to get rid of particle restriction/clogging.

If flow is restricted to the washing machine......there should be screens inside one end or the other of the supply hoses. Find 'em and clean 'em.

If particle obstruction isn't the flow problem........

What size pipes did you run during replacement?

Reason you replaced all the plumbing was......? ...poor flow? If so, then I'd look back at the street flow (not pressure)......and/or at the fixture restrictors.

Also.....water delivery to the second floor is fighting gravity. Reduced flow is the result.

Combo of... restrictors....and/or... too small of pipes... and/or....poor supply flow will result in reduced flow everywhere, but more so on second floor fixtures (the gravity thing again).

Long runs or runs with numerous turns and twists will also have reduced flow. Friction reduces flow.

New shut-off valves in the new plumbing runs? Globes, gates or ball valves? If ball valves are they full-bore valves? Type of valve effects flow thru the valve. Best type is full-bore ball valve.

Where is the nearest place in the plumbing to the street supply that you can easily disconnect to check flow? Disconnect and catch water in a bucket or similar while you time it. How many gallons per minute?

Is there a PRV (presssure reducing valve) in the supply line coming from the street? If so, the screen may be plugged or valve needs readjusting or replacing.

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