Fitting copper water supply pieces together

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dogpal

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Issue:
I’m asking for help with:
1. Replacing the main water supply valve
2. Adding a pressure reduction valve, and
3. Replacing the hose bibb
all located at the front of my house.

Background:
Single family home built in 1991, the city water meter is nearby and adjacent to the sidewalk in front of my house, the 1” city copper water supply line runs up to the front of my house just east of my front door. Above the water supply’s point of connection to my house, there is a failed 1” main supply gate valve, then above that is a tee to a 3/4” copper line for supplying the house’s fire suppression system, then up from that is a tee to feed the house’s water supply and to a failed hose bibb. All of this plumbing is clearly visible and easily accessible right outside the stuccoed exterior of the house’s front.

My plan (from the point of connection up):
1. Replace the failed 1” main supply gate valve with a 1” ball valve.
2. Install a pressure reduction valve.
3. Install a new tee to supply the fire suppression system.
4. Install a new tee to feed the home’s water supply and the failed hose bibb.
5. Install a new hose bibb (one that threads on and isn’t sweat soldered in place like the current one).

I’m comfortable/experienced with sweating copper pipe.

The copper line for the house’s fire suppression system and the copper line for the house’s supply/hose bibb piping/assembly above it are rigid in place (little if no ability to move/bend slightly).

If you were standing and facing the hose bibb (it is about 3’ above the ground), you’d have the failed 1” main supply gate valve’s handle facing your ankles and the line supplying the fire suppression system at about knee level but directly left (or left 90 degrees) from your knees. So...
• The 1” city copper water supply line is rising out of the ground.
• The line supplying the fire suppression system goes off to the left into the wall of the house.
• The line for the house supply/hose bibb is straight ahead and travels into the wall of the garage.

Question:
What is the technique to get the two tees|pressure reduction valve|ball valve situated in place to sweat when I seem to have little ability to move the existing piping in order to get all of the pieces to fit together? What I’m talking about is...I don’t (of course) want to have everything sweated in place and a 3”-4” gap and say, “Gee, how am I gonna slide this short piece of copper pipe in between these last two connections? Make sense? Am I missing an obvious solution? Yikes.

Thanks for whatever help is offered on this-
 
Use of a "Union" on each end of the gap will allow you to slide a piece into the gap to complete the repair.
 
I think the part of the puzzle you're probably missing is something called a "slip coupling".

A slip coupling has no "stop" on it to prevent it from sliding onto a copper pipe. So, if you find you've got a 4 inch gap in the piping, you simply:
a) sand the ends of those pieces of pipe and flux
b) brush out two slip couplings and flux
c) slide the slip couplings onto the ends of the pipes
d) sand and mark the ends of a 4 inch pipe where the ends of the slip couplings should be and flux.
e) put the 4 inch pipe in place and slide the slip couplings into place
f) ensure there is a path for the air inside the pipe to escape as the pipe is heated (other than through the joint's you're trying to solder), and
g) solder the 4 inch pipe in place.


About plumbing the pressure reducing valve:

I would plumb it in the following sequence of hardware:

1. A ball valve to shut off the flow upstream of the pressure reducing valve
2. the pressure reducing valve
3. a pressure gauge
4. another ball valve to shut off the flow downstream of the pressure reducing valve.

The two ball valves allow you to replace the pressure reducing valve without having to call the City to shut off the main supply valve to your house. Having the pressure gauge and shut off valve downstream of the pressure reducing valve allows you to shut the downstream valve and then adjust the pressure reducing valve to give you the pressure you want in your house showing on the gauge. Then open the downstream valve. Because the amount of water that has to flow into that small volume is tiny, you'll get an instantaneous response on the pressure gauge as you adjust the pressure reducing valve. If you overadjust the pressure too high, just open the downstream valve and a faucet, and the pressure will drop, and you can try again.

The most common cause of solder joint leaks is trying to solder a joint without providing a path for the expanding air inside the pipe to escape. Since it's capillary pressure that draws solder into the solder joint, the greater the air pressure inside the pipe that's trying to push the solder out of the joint, the more problem you're going to have getting that joint to take solder.

Hope this helps.
 
PS:
If the home centers where you live don't sell slip couplings, and only have the "dimple stop couplings", you might get some retard telling you to just take a round file and file the dimple off the ID of the pipe, thereby allowing you to slip the dimple stop coupling over the pipe just like a slip coupling.

This is terrible advice.

The reason why is that the dimples on dimple stop couplings are often almost as deep as the wall thickness of the coupling. So, if you file off the dimple from the ID of the pipe, the wall thickness where the dimple is could be almost zero. If that dimple is right over the joint between two pipes, you can have a potential leak even if the soldering goes well.

The better advice would be to insert a socket or round metal bar into the dimple stop coupling and hammer the dimple out of it. That way, you don't reduce the wall thickness at the dimple location, and the coupling's pressure holding capacity is not compromised.
 
Thank you.

Union/slip coupling - *that* was what I was missing. It is all coming back to me now (has been more than a few years since I was working w/copper water supply pipe and swapping pieces in and out). Makes perfect sense. Thanks for the step-by-step to put that final piece of copper pipe in place.

Great point about providing a path for the expanding/heated air to escape. I suppose that the new hose bibb with the stem assembly removed and just open to the atmosphere would suffice...?

I’ll have to look at the current set-up more closely to see if I have room to put in line a second ball valve and a pressure gauge on the main supply line. In Phoenix, Arizona incidentally, there is no need to call the City to turn the water off. I can do so myself using a small adjustable wrench and by going to the valve/meter in the box next to my driveway/the sidewalk. That is precisely what I have been doing since the gate valve for the main supply line at the house failed.

What’s the recommended fuel for sweating 3/4” and 1” copper pipe? MAPP gas? Propane? I’m not going to have an acetylene set-up available for doing this job. Hand-held torch will have to suffice. Suggestions?

Thanks for the great help-
 
Propane works fine for Type "M" copper pipe and MAPP is preferred for Type "L" copper pipe. I use MAPP for both, it just makes the job easier without heating up more than what's necessary.
 
DogPal:

I use propane for everything; 1/2 inch, 3/4 inch, Type M, Type L. The important thing isn't what fuel you use, but to use a torch that mixes the fuel and air prior to igniting it. That principle (which is used on bunsen burners) is what gives you a much hotter flame, and that results in both faster soldering and more reliable solder joints.

I only use Type L copper pipe in my building. Whenever I replaced the pipe going up to the shower arm when renovating bathrooms, I replaced that 4 foot length of Type L with Type M cuz there's seldom any pressure inside that pipe, and when there is, it's not even full supply line pressure. So, I have lots of 1/2 inch Type L copper pipe that I can use for piping that's gonna be under full supply pressure all the time. I can't say I like Type M copper pipe all that much anyhow. I prefer L. It has a thicker wall, so there's less chance of it going out of round if you're fighting with a hot fitting to get it off or something.

ANY opening in the copper piping you're wanting to solder that's larger than a pin hole is more than adequate to allow the air pressure to escape. An open valve is plenty big enough. It's not that people don't provide a large enough hole for the air to escape; it's that it doesn't even cross their mind that heating the pipe will increase the pressure inside it, so they don't provide any path for the increased air pressure to escape, and that's what prevents the joint from taking solder. And the smaller the enclosed space, the more important it is to release the air pressure.

I’m comfortable/experienced with sweating copper pipe.

If you say so.
But, it's OK to admit you don't know how to solder in here. Lotsa newbies don't.

Click on this link and read my post about the steps involved in soldering and why each one is important:

http://www.houserepairtalk.com/f33/basic-soldering-copper-pipe-7192/

I think you'll find it an interesting read.
 
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Thanks for the additional information.

it's OK to admit you don't know how to solder in here. Lotsa newbies don't.

Click on this link and read my post about the steps involved in soldering and why each one is important:

http://www.houserepairtalk.com/f33/basic-soldering-copper-pipe-7192/

I think you'll find it an interesting read.

In fact, that was the first post I ever read on HouseRepairTalk.com. Very informative and useful.

I sit behind a desk all day to earn a salary and don't work on plumbing for a living. I grew up living in a falling apart seven bedroom/3 level house built in 1932 and because we didn't have much money, we (usually me and my father) had to fix all of the (constantly failing) plumbing (i.e., galvanized, cast iron, and copper) ourselves. I was sweating pipe at 14 or 15 because I could fit in the trenches and the crawl spaces where my 220 pound father couldn't. It has simply been a couple of decades since I was regularly doing plumbing in order to earn my keep ;-)

Perhaps it is my use of firearms and rebuilding of Mercedes-Benz engines: I have a tendency to be extra careful and ask a lot of questions before I put tools and materials in my hands and start taking action.

On a different subject...
Given the size of the PCV and the 1" ball valve, I see that it is going to be a fairly tight fit given the current configuration of the piping at the front of my house.

Question:
Is there a minimum pipe length for situating between, say, a tee and a valve or is it more a matter of, "If you can get the flame on it, pipe length is nothing to be concerned about."?

Thanks-
 
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Question: Is there a minimum pipe length for situating between, say, a tee and a valve or is it more a matter of, "If you can get the flame on it, pipe length is nothing to be concerned about."?

It's the latter. If you've got enough room to solder it, that's all that matters.

However, I like to leave a gap of about 1/4 inch minimum between fittings so that you can see if there's a silver ring formed at each joint. If you have no pipe between the joints, you won't be able to see the formation of that silver ring even when it happens.

(Also, I like to clean the black "tar" (burnt flux) off my solder joints afterwards and check them with an inspection mirror before turning the water back on, and having them separated by at least a quarter inch helps me do that.)
 
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Makes perfect sense.

Thanks to those who posted their help and advice for my project. I appreciate it.
 
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