Main Shut Off Valve Questions (w/Photos)

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Years ago they use to come in the house and read the water and gas meters. Until they put remote readers in. Where I live you can't
request a different size meter for a 3/4" line. There all the same size meters. 1/2" IPS spuds. We are responsible for the main water
line from the curb box to inside the house. That includes the main shut off valve. We are required to have a valve before and after
the meter.
Exactly the same for me. With the exception of the valve downstream of the meter. But I think that's a good idea.
 
So if the meter is only 1/2” why is anyone concerned with 3/4 trunk lines? Your only going to get 1/2” flow so why waste the money on larger pipe? Ours are all 3/4 here to supply a code standard house 3/4 flow. But some still put 1” from meter to house. But aren’t you still gonna get only 3/4 flow?
 
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So if the meter is only 1/2” why is anyone concerned with 3/4 trunk lines? Your only going to get 1/2” flow so why waste the money on larger pipe? Ours are all 3/4 here to supply a code standard house 3/4 flow. But some still put 1” from meter to house. But aren’t you still gonna get only 3/4 flow?

Meters are frequently one pipe diameter smaller, so they are more accurate at low flows. And, like any other impediment to flow, the water sees the smaller meter as a head loss, which while it throttles the flow a bit is actually a small part of the total head loss.

The flow from low to high is within the range 0.1 to 20-gpm of the 5/8-inch meter, and if the whole run was 1/2 or 5/8-inch, the pressure drop would be significant.
 
So if the meter is only 1/2” why is anyone concerned with 3/4 trunk lines? Your only going to get 1/2” flow so why waste the money on larger pipe? Ours are all 3/4 here to supply a code standard house 3/4 flow. But some still put 1” from meter to house. But aren’t you still gonna get only 3/4 flow?
Pressure loss due to friction is by the foot of length or it's equivalent. A 5/8" water meter could have about 1 psi pressure drop at 5 GPM while a 1/2" type L copper pipe would lose about 17 psi per 100 ft of pipe length. 3/4" copper would be about 3.2 psi per 100 ft of pipe length.

EDIT: Like FishScreener said before I hit enter on my keyboard, the meter is actually a small part of the total head loss.
 
So I can get 3/4 flow threw a 1/2 meter as long as I put 3/4 on both sides of meter?
 
Everything that is in a system contributes to the total head loss. The length of the run of each size of piping, the meter, every bend, every fitting has an associated pressure drop.

When you start calculating the head loss it is kind of difficult to narrow it down to a specific value. Because it varies with the volume of flow, and the volume of flow varies with the head loss.

But, in general: At typical flows the meter being one size smaller than the line will have a very slight effect on the total head loss, because the friction losses in the pipe, valves and fittings will be so much greater than the loss of just the meter.
 
Huh. That gives me experiment ideas this weekend. I have a 1/2 , 3/4 and 1 meter. My house meter is 3/4 so I will go to a moms factory to get a 2” supply. 50 gallon drums and a timer? Anything else I might need? I just finally have to prove it to myself. Been wondering for many years why people ty in a 2” line past a 3/4 meter.
 
For true. Here in the frozen northwest, our 1929 house has a shutoff valve at the curb. The incoming line is about 6' below ground, with an iron stub bringing the pentagon-shaped valve stem up to a bell topped with a plate; theoretically, the water can be shut off with that valve. Practically, if the city tries to use the nearly-100-year-old valve, many no longer function. The meter always was in the basement with the original 1" valve before the meter. When the utility was converting to remote read meters, I asked for and received an upgrade from 1/2" to 3/4" meter at no charge. The old 1/2" meter was much louder in operation than the new 3/4"; maybe just newer tech.

Post-WWII construction here has the meter at the curb about six feet down in a manhole.

(And yes, the OPs is as ugly and low-budget water service as I've seen. Is it actually in an incorporated area with code enforcement and inspection?)
 
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Huh. That gives me experiment ideas this weekend. I have a 1/2 , 3/4 and 1 meter. My house meter is 3/4 so I will go to a moms factory to get a 2” supply. 50 gallon drums and a timer? Anything else I might need? I just finally have to prove it to myself. Been wondering for many years why people ty in a 2” line past a 3/4 meter.
You're going to get substantially more flow through the 3/4" meter over the 1/2" not in a piping system. But you have to think of it as having a similar impact on the system as a 3/4" globe valve. Just one item adding a bit of pressure loss but still a 3/4" piping system. ( I know, you wouldn't use a globe valve.:D)

Another way to think of it would be if you put 2 vertical 3/4" lines straight up, open ended, one with a 1/2" meter and one with a 3/4" meter, at the same flow rate of say 10 gpm, the 3/4" meter system would be capable of pushing that 10 gpm up about 1.2 psi or about 2.8 feet higher. Same flow!

The 1.2 psi came from looking at the difference of pressure loss through a typical 5/8" and 3/4" meter. See below...
 

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For an accurate assessment of the impact of the meter, in a system, run the test with two hundred feet of 3/4 inch hose between the valve, and the meter.
 
For an accurate assessment of the impact of the meter, in a system, run the test with two hundred feet of 3/4 inch hose between the valve, and the meter.
Good approach for a hands-on type of guy like James.
How many people have 200 feet of 3/4" hose, besides me?:D
 
Me too. Lol ok I gonna try it. Another thing I wanna test is 2” pipe 20’ plumb vs 3/4” 20’ plumb. I am betting the 2” just bubbles over while the 3/4 continues to push higher. To show how to big of a opposing line can absorb a lot of the pressure and cause it to flow slower than just running at most 1” on a 3/4 meter. But around here for long supply lines. Like I mean in the thousands of feet. They will in form this increases flow. But I have to step in and ask for a 1” meter and run 1”. I have ran 2500’ like this and still had to have a reducing valve at house. But the original 2” had the reducer at meter. So once that large volume got depleted the loss was very noticeable. So I started by putting prv at house. This exposed every bell joint had been glued with “wet or dry cement”. The deep blue. And no cleaner marks or purple. So I dug up every 300’ and sleeved 1” the whole way. Now they have to have a reduced at meter bringing field hydrants down to 120 psi and 1 at house at 65 psi. The guy likes it lower. But never had utility district out to install 1” meter so. This was interesting enough to bring that back up
 
there is another way you can install a new valve …..leave that one before the meter alone ….if your not comfortable soldering or there is to much wter passing thru the valve there is something call a compression ball valve they are pretty expensive but work well I usually put an f+m ring behind each nut so there is no chance the nuts can loosen up
 
Me too. Lol ok I gonna try it. Another thing I wanna test is 2” pipe 20’ plumb vs 3/4” 20’ plumb. I am betting the 2” just bubbles over while the 3/4 continues to push higher. To show how to big of a opposing line can absorb a lot of the pressure and cause it to flow slower than just running at most 1” on a 3/4 meter. But around here for long supply lines. Like I mean in the thousands of feet. They will in form this increases flow. But I have to step in and ask for a 1” meter and run 1”. I have ran 2500’ like this and still had to have a reducing valve at house. But the original 2” had the reducer at meter. So once that large volume got depleted the loss was very noticeable. So I started by putting prv at house. This exposed every bell joint had been glued with “wet or dry cement”. The deep blue. And no cleaner marks or purple. So I dug up every 300’ and sleeved 1” the whole way. Now they have to have a reduced at meter bringing field hydrants down to 120 psi and 1 at house at 65 psi. The guy likes it lower. But never had utility district out to install 1” meter so. This was interesting enough to bring that back up
You have to remember that you'll always need a PRV if the supply pressure exceeds the allowable "static" pressure. You can have 1000 feet of 1/4" pipe(an exaggeration) and the "static" pressure will still be the same at both ends. It's when it gets moving that you start losing pressure due to friction loss. The higher the GPM the higher the friction loss. So to counteract the pressure loss (and resulting flow) you increase pipe size to reduce friction loses. The longer the distance, the more the friction loss, and the larger the pipe must be to obtain the desired flows with still some usable pressure left.
 
Ahh dang women. We got “more important’ stuff to do today. Where’s that teacher that needed projects.? This would great for them. I just need a day without the women around.
 
I was faced with a similar issue when I received a notice from my water company that I needed to schedule a meter upgrade earlier this year.

I'm in upstate NY and our meters are inside with a wire running out to a small plate on either the siding or foundation. When they changed my meter they also upgraded the outdoor plate so that they can read it remotely from the street instead of having to walk up the driveway.

I also wanted to have my old shutoff replaced and hired a local licensed plumber.

I was insistent on having a ball valve type of shut off and wanted something heavy duty.

My plumber was hesitant on the phone but once he stopped by to price the job he found a AY Mcdonald valve locally for around $90 after I gave him a link for a Mueller valve.

A week before the meter was scheduled to be changed he came by and replaced the old shut off and put in a ball valve shutoff after the meter. He also re-plumbed a little bit to get the pipe that was off the wall by 12 inches against the wall, which enabled placing the secondary shut off low by the meter.

I had a 3/4 copper line entering the basement in my 1957 built house and the new valve needed to be installed with a flared end to the copper for code in my area.

At first my plumber wanted to leave the old valve, but after seeing my set up he agreed to flaring on the AY Mcdonald valve for me.

1st pic is after both the meter and new valves were installed and the 2nd pic is my original setup.

I'm not a plumber, but I do my own plumbing at home and didn't hesitate to pay a professional for this job.

Including the pricey valve, it cost me $225 and took my plumber about an hour.

New shutoff and new meter1.jpg

Old shutoff and old meter.jpg
 

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