Replace PRV Gate Valve in Ground

[catchlizzy]

Hello everyone! I need some advice to replace a working PRV (identical unit but lead-free PRV) and gate valve with ball valve for my main water line. I want to replace all components to lead free and make them easily replaceable. My intention is to make future maintenance/replacement as straight forward as possible. My water main is buried 1' underground in my front flower bed. This is what I plan to do ...

1. Cut existing 1" copper tee where the gate valve is attached
2. Test fit the new PRV with dual unions, ball valve from house main pipe to the city main pipe
3. Mark the proper length to cut in the house main water pipe
4. Cut the main water pipe leading to house
5. Do one of the following...
a. Either sweat new copper tee directly to water main line leading to house
b. Sweat in male adapter to water main line leading to house
6. If step 5b. sweat in female adapter to new copper tee (to connect to male end of main water line created from step 5b).
7. Install copper tee, ball valve, PRV to city line

I would like to know what the experienced people think of my proposed solution? Suggestions? Am I having too many joins and complicating the configuration of my water main?

I have attached pictures of the existing setup and the new proposed setup.

 

[Reach4]

Would it make more sense to put the valve before the PRV?

 

[Sponsor]

 

[catchlizzy]

Would it make more sense to put the valve before the PRV?

I thought about putting in another shutoff before the PRV but it may be too long for the meter box. Currently before the PRV there is a city shut off valve in the street main cover.

 

[hj]

Use a PRV with double unions and forget about all the gyrations to make it "modular".

 

[catchlizzy]

Use a PRV with double unions and forget about all the gyrations to make it "modular".

What the risks of having too many joins like unions? Are there best practices for how many to use, how many is too much? I also have the limitation of overall length as the finished product has to fit into the valve cover box.

 

[Reach4]

I also have the limitation of overall length as the finished product has to fit into the valve cover box.

If that is a problem, you could put in a larger valve cover box.

This total lack of flex when trying to insert some things in line seems like a problem. I would think you might need a repair coupling or a jog, but maybe that double-union PRV makes it work without either of those.

 

[catchlizzy]

If that is a problem, you could put in a larger valve cover box.

This total lack of flex when trying to insert some things in line seems like a problem. I would think you might need a repair coupling or a jog, but maybe that double-union PRV makes it work without either of those.

I will put in another union from PRV to brass coupling which connects the ball valve. I will also sweat in a male fitting after cutting off the existing tee. I'm fine with making multiple turns to screw in the ball valve. I am concerned that if I install two unions between the ball valve, the movement of the ground (all gray clay in north Dallas area) could compromise the union joins. What do you think?

 

[Reach4]

I am not a plumber. I don't know the best practices. http://www.thermacor.com/wp-content/themes/thrma/flat-theme/pdf/technical-data/15.103-4_001.pdf talks of an expansion elbow, z-bend, or loop. It seems to me that if you measured in inches rather than feet, it could scale.

 

[hj]

the unions are built into the PRV, just like the ONE on your existing prv. They do NOT take up any room in the piping.

 

[Reach4]

Below is a Honeywell PRV with double unions. I picked this picture because it has the pieces separated in the photo. It seems to me that when you remove an old unit and replace the main piece with a new identical working unit, you would want a little flex in line with the pipe axis.

Even if you picked a unit with no o-rings, but with metal-to-metal, you might still need some give to get it in and out. An elbow nearby could give a little flex. If everything is on the same axis, no flex.

 

[catchlizzy]

Below is a Honeywell PRV with double unions. I picked this picture because it has the pieces separated in the photo. It seems to me that when you remove an old unit and replace the main piece with a new identical working unit, you would want a little flex in line with the pipe axis.

Even if you picked a unit with no o-rings, but with metal-to-metal, you might still need some give to get it in and out. An elbow nearby could give a little flex. If everything is on the same axis, no flex.

First of all thanks everyone so far for chiming in and giving me insights.

The PRV I'm replacing is exactly like the existing, except it's lead free. Both came with only one union. I will add an additional union to connect to a brass pipe nipple (1 in. MIP x 3 in.), which joins to the new ball valve. I plan to add a male thread fitting to the copper leading to my house so I can screw on the 1" copper tee...or should I add a metal-to-metal union to connect the tee to the copper pipe incoming to the house?