plumbing - main water line repair

[Coloradotrout]

I have a 15 year-old home.

Water line between street(meter) and home was leaking (line is about 60 feet).

A large sinkhole developed. I dug down 7' to find the solid copper line from the house joined to PVC. The connection was as follows.

3/4" copper line from house (10') --> brazed to 1" female connector --> 1" male nipple w/ threads to 3/4" male threaded fitting (solid brass) --> PVC 3/4" female thread to 3/4" slip --> 3/4" pvc pipe

The PVC slip connector sheared off. All of these are RH threads, and no unions. So it all had to be assembled sequentially.

How do I fix this? The right solution in my mind is to run a new trench and lay continuous copper. I don't believe that is feasible. We are looking to spend another 1-2 years here. But I hate leaving anyone a problem waiting to happen. Going to Lowes/HD, the best I can come up with is:

3/4" copper line from house --> 3/4" union --> short copper pipe --> 3/4" male thread adapter --> 3/4" PVC female thread adapter to slip --> pvc pipe

The original solution was 4 joints. The above is 6. Thoughts? (would a

3/4" female adapter --> 3/4" male pvc to slip be better)

I can do basic sweating of copper. But I've never brazed. Should my copper joints be brazed?

Thoughts? Ideas? Volunteers (just kidding.. at least half way)

[DerbyDad03]

Do you know what you own vs. what the water authority owns? Is it possible that the water authority is responsible for the PVC section and it's their responsible to fix it? Perhaps at sometime they replaced their old copper with PVC up to the point where the homeowner owns the rest.

That's what they did with my sewers a few years ago, so maybe it's the same wih your water.

[Coloradotrout]

The own up to the meter. Unfortunately this section is between the meter and my house. They would not even come out and locate the line. Fortunately the sink hole was right over the leak.

[Speedy Jim]

No need for brazing. The PVC is the weak link here, weaker than soldered connections.

BUT.....DO use a PVC Male adapter going into a Female copper adapter. That will be waaaaay stronger than using a Female PVC (as you suspected).

You can avoid the PVC slip joint. Get a copper "repair coupling". This has no internal ridge and can be slipped over the ends of 2 pieces of pipe. If you can, move this splice back from the PVC connection a foot or so to keep from heating the PVC. The copper Female adapter can be soldered onto a short length of copper working outside the trench.

Another approach would be to put a 3/4" Union in the line. Normally, one wouldn't bury a union in the service, but given all the other connections, I don't see it making any difference.

Jim

[Larry]

You were fortunate to find the leak withouth having to dig up more of the pipe. If you go to a regular plumbing supply house they will likely be able to supply you with a solution using a minimum of fittings. Since the house is only 15 eyars old, and presumably the pipes in question are the same age, I would not feel bad about just fixing the leak instead of replacing the entire run (Unless you are in an area where the water quality is known to be a problem for copper) Soldering to the copper pipe whould be fine. Just make sure that you thoroughly clean the pipe ends before sweating or installing the fittings, and don't backfill for a few days so you can make sure the leak has been repaired.

[Coloradotrout]

Not quite sure I follow how that removes the slip joint ( slip joint may be the wrong words, I meant a pvc glue joint) but let me see if I have the idea.

1 cut off the 1" male (receptor of nipple connector) from the copper, polish the pipe 2 cut/clean the pvc end 3 so now I have in the hole a 3/4" copper pipe and 3/4" pvc about 12" apart 4 now take a 3/4" female copper adapter and sweat it onto a piece of 3/4" pipe about 12" long 5 glue on a 3/4" pvc male threaded adapter to the pvc pipe 6 slip a no-ridge copper coupler over this piece 7 put this assembly in the hole 8 cut the copper pipe 'to fit' 9 tighten the copper female adapter onto the male pvc thread (step 5 above) 10 slide the no-ridge copper coupler to the center of the copper gap 11 sweat both sides into place

so I'd have..

copper line | copper coupler (no ridge) | new copper pipe | copper female threaded adapter | male pvc adapter | pvc pipe

So if I count the | above, that is 5 joints - 3 sweat, 1 thread, 1 pvc glue. Better than the 6 with my union idea below! Not as good as the 4 joint original, but I see no way to do that without running new line (and at

6' plus in the dead of winter, that's not an option).

Maybe now to add strength, I could use a 1" joint on the PVC side. Upsize from 3/4" to get more plastic?

What about using those premade cpvc to copper adapters? I could pvc glue that to the pvc pipe and have a male copper thread to feed into my female copper adapter? Would that be any better than the male pvc to female copper connection? (Personally, I'm a bit leary of those cpvc-to-copper fittings, but I could be wrong.)

How can I pull the heat off that copper pipe while I'm sweating the splice so it does not melt the pvc? A wet rag?

Any tips to get that male pvc to female copper joint as tight and strong as possible? Use a copper/pvc thread sealant? Any other ideas?

When I backfill the hole, I think I will firm up the soil as much as possible under this, so when the soil from above settles, hopefully it will not apply so much of a load that the "fix" bends/breaks. Thoughts on this?

What kind of PVC glue?

If this was above ground or even 3' under, I'd be a lot less cautious. But at nearly 7' I dont want to repeat this exercise for awhile.

[Coloradotrout]

Jim,

After thinking about this for a bit, maybe the pvc female -to- copper male is stronger?

A pvc male will be limted to the thickness of the material less the material removed for the threads. A pvc female however, can be as thick as it comes with the material removed from inside of it.

Just thinking that a pvc male adapter is going to be pretty thin material. The pvc female could be pretty thick.. well.. at least to thickness of the manufacturer.

[DanG]

These things are great. We have gone to them exclusively on repair work. You probably will not be able to buy them at a regular plumbing supply house. Most sprinkler and irrigation companies have them:

It does sound like you need to bush up or down on one line size or the other.

[Coloradotrout]

Wow.. I can't imagine putting something like that into a 7' underground ditch for my mainline. I'm thinking simple=best.

I need to join a 3/4" pvc to 3/4" copper.

[dpb]

On Jan 28, 3:20 pm, "Coloradotrout" wrote: ...

What I'd suggest there is to put an arch over the joint out of block or other to provide some relief around the joint area resting on the trench bottom then fill. That should keep any direct movement from causing the joint to move.

Until you said that, I was going to suggest the alternate way to replacing the line to the street could be to have only a PVC joint in the trench and run it to the house for the transition to copper inside.

[Speedy Jim]

No. The problem is that the threads are tapered. As you tighten your male copper fitting into the female PVC fitting, the taper forces the PVC to expand until it cracks (maybe not immediately, but certainly after the hole has been backfilled )

[Speedy Jim]

Yes, you have it right.

Use a wrap of Teflon tape on the male threads. No need to overtighten.

Damp rag to control heat.

Lots of flux on the surfaces to be soldered (after thorough polishing).

You could build some flex capability into it by making a "U" out of copper and fittings (put the "U" upside down). Better yet, make your stub of copper pipe out of Type L soft copper tube. Make it longer than 1 foot if possible. Soft tube will flex quite a bit.

For the truly paranoid, a section of stainless braided hose would be perfect!

Jim

[zxcvbob]

Cut off a 3" piece of the copper pipe to use as a nipple, and cut off the broken PVC fitting. Buy a section of 1" PVC pipe, a 1" copper FIP fitting, a 1" copper repair coupling, a 1x3/4" PVC reducer coupling, and a 1" MIP fitting.

1" copper pipe -> repair coupling -> copper nipple (cut from the copper pipe) -> copper FIP -> PVC 1" MIP -> short 1" PVC pipe -> PVC reducer coupling -> 3/4" PVC pipe. Connect the copper repair coupling last. ;-)

Regular lead-free solder should be just fine. Use purple primer on the PVC glue joints.

If you are paranoid, buy some soft copper (like Jim said) make a loop or an S and use that instead of the short copper nipple and the long PVC nipple, so it can expand and contract without stressing the PVC joints.

I'll bet this could also be done neatly with soft copper and a flare fitting instead of the repair coupling.

Best regards, Bob

[Coloradotrout]

I may have confused this a bit.

The copper from the house is 3/4". So I need to go from 3/4" Cu pipe to

3/4" pvc.

So I think Jim's point was..

3/4" Cu mainline | Cu repair coupling | 3/4" Cu pipe (length cut to fit, or use soft and make S or U shape) | female Cu adapter | male pvc adapter | 3/4" pvc

All the above are 3/4" pipes and fittings.

It looks like you were thinking I had a 1" Cu pipe from the house. The original had a 1" female adapter brazed to the 3/4" line. Then a brass 1" male to 3/4" male (threads both ends, the 1" end had a compression-like fitting to that 1" female adapter), then a 3/4" pvc female, then the 3/4" pvc pipe. There were all RH threads, so it was assembled sequentially. Can't do that now ;-)

It's probably best to cut off that initial fitting and use the repair coupling. At least that is my thought.

I do like the idea of a short run of flex copper.

[Coloradotrout]

Ahh.. makes sense.

It looks to me like the orig>

suspected).

[Coloradotrout]

Yeah,thinking since I about have a 4'x8' hole that is 7' deep, I should just lay down some cinder block walls and add a door. LOL

I definitely will let is 'sit' a few days. But our overnight temps are in the high teens, so I need to figure out some way to insulate the hole for a bit. Any ideas?

[zxcvbob]

I thought you had 1" from the house, joined to 3/4" from the meter. Make sure the flex copper (you mean soft "L" copper tubing, or flex like a gas line?) is OK for direct burial. The flexible section needs to be bent into a snake or something. If it's perfectly straight, it can't provide the necessary slack if it needs to stretch.

Best regards, Bob

[BobK207]

the house, joined to 3/4" from the meter.

I don't think I'm following the thread very well but ......

I would suggest doing all the repairs in PVC.

The best is a male PVC thread into a female copper fitting, if I read everything correctly you have a threaded female copper fitting in the mix somewhere.

If you have enough PVC exposed you can bend it out of the ways such that you can use a PVC slip (glue coupling to make the lsat PVC connected.

File out the stop in the PVC coupling such that it slide all the way passed the end of the pipe when glue is applied

Gotta work fast.......

prime both ends of the PVC to be joined AND the coupling slather up the pipe ends w/ glue, then the coupling then a quick recoat on the pipes slid the coupling on passed one pipe align the pipe, slid the coupling to center position & give it a1/4 twist to smear glue

like I said, you gotta work fast! no margin for error.....but you can always cut it out

If you've never done one of these I suggest a practice run with scrap material.

I'd insulate the hole...a couple layers of cardboard or burlap will work but I'd add a 100 watt light bulb to the hole since you're gonna get down into the teens.

cheers Bob

cheers

[Larry]

Man, that's a tough one. I didn't think about it getting that cold in your area. Is there any way you can leave the pit open til the spring? Maybe you could make a temporary repair using rubber hose. Years ago I owned a house with 2 apartments. I lived in the upstairs unit. The same pipes served both apartments, running inside walls and ceiling of 1st floor apartment to serve the 2nd floor.

One winter when the first floor unit was vacant, I had pipes burst in several places. Every time I repaired a crack (copper) and turned the water back on, I'd find another crack 2 or 3 feet further down the pipe. After a while I got so frustrated I went to an auto parts store and bought 20 feet of heater hose, which I used to make a temporary repair that I left in place for several weeks.

Not sure about insulating the pipe overnight. I would guess that if it adequately below the frost line, maybe covering it in several layers of fiberglass batting insulation would work. Hope somebody has a proven idea that will work for you.

Do you have any water to your house now, or did you have to shut it of at the street? Good luck to you!

[Coloradotrout]

Bob, Thanks.

It's pretty simple really I'm beginning to think. Basically, when I cut away the remains of the original joints, I'll have 3/4" copper and 3/4" pvc about 12" apart. I need to join the two together. Another poster sorted it out for me. Sweat a female threaded fitting to 12" or so of 3/4" Copper pipe. Screw in a 3/4" male pvc fitting. Take that into the hole, test fit, and cut the copper to length, and slide on the copper repair coupling fitting. Glue the pvc fitting to the pvc pipe. (I figure I may as well screw in the pvc male fitting to the copper female while I'm out of the hole and can work with it more easily.) Now slide the coupling over the two copper pipes and sweat 'em together. That's probably as good as it's going to get. Alternatively, that 12" or so of ridgid copper could be 18" or so of flex (not the water heater stuff, but rather the stuff that can come in big rolls) with an S shape. That would give the whole assembly some "flex". I like that idea.. kinda like a shock absorber, and it's the same number of joints.

compression-like

sequentially.

from the house, joined to 3/4" from the meter.