Need advice: Connecting pvc to gal steel pipe

[Al Kondo]

I had a break in the main water line feeding my house yesterday. After digging a hole where the line comes out of the ground and comes into my house, I found the leak in the pipe at the elbow where the vertical run of the pipe turns horizontal. Here is my question.... After talking to a very knowledgeable friend, I decided to converted some of the pipe from gal steel to pvc. The installation seemed to be much easier and I was told that it would be very durable.

Here is my problem.... After putting all the pieces together, I am finding that I am having a very small leak where the pvc pipe joins the gal steel pipe. I am joining the pvc to steel via a fitting that is female threaded (on the pvc fitting) where the pipes join and smooth on the side where the pvc pipe fits. At the threaded end, I am using teflon tape and I screwed it into the gal steel threaded end with considerable force. Yet, it still has this very small leak. What do you suggest that I do??

Al Kondo

[Speedy Jim]

That's called a "female adapter". They are generally not used on pressurized lines because the tapered pipe threads will tend to crack the adapter, leading to a BIG leak.

Better is to use a male adapter and put a steel coupling on the pipe.

I should add that the water service line is alomost certainly used as the grounding electrode for the house elctrical service. The section of PVC will interrupt that ground. Best install a bonding jumper around the PVC and ensure that the connections for the jumper won't corrode.

Jim

[PAUL100]

I have had the same problem as you have. What i have done is to not over tighten it. Just put it a litttle past hand tight and use plenty of teflon tape.. I think the pvc threads distort when you tighten it to much.

[redneck69]

Duct tape !!!!

[handyman]

If this is underground, the OP is asking for troubles. That pvc will crack when the ground shifts from freezing or other shifts in the soil. I'd just replace with the same material, which was galv. steel. Copper would also work, but requires dielectric unions, which defeats the grounding again. Personally, I would just use steel again. It probably lasted 30 years before and will last another 30. The PVC will probably last 2 years or less. To me, all that work digging is not worth the little extra effort and cost to use steel again. Besides, what is so hard about using steel. Just measure what was there, have a plumber or hardware store cut and thread the pieces, buy new elbows and fittings, and screw it together with teflon tape on the theads. What's so hard about that?

If you cut out a section, just use a union, preferably above ground. Best yet, inside the house at the entry point.