[cbzdel]

I need to remove a old pipe on my house so I can replace it with a di-electric union and convert it to copper pipes. I am fairly certain the pipes are original, meaning 70 years old. I dont know how to tell the difference between steel or iron pipes but regardless I need to remove a pipe coming off of a "T" (if looking at the letter to the left and imaging pipes it would be the vertical pipe)

I keep hearing old pipes are brittle. So how can I remove this pipe without ruining everything? This pipe come off the main water line in and the only off valve for it is at the street, so its got me a little worried what if it just crumbles when I put the wrench on it and I am stuck with a broken pipe and no way to turn the water back on.. I just keep thinking this and all I see are $$$$$

When installing the new fitting is pipe dope or Teflon tape preferred?

 

[WDR]

You might be able to unscrew it with out a problem but it will more likely crumble like you thought. If you decide to do it as far as tape/dope I think just dope or a combination of the two is best.

 

[plumber666]

Replacing ALL the old (likely galvanized steel) pipes is the only proper solution. Chances are, because they're old and corroding, the pipes threads will break off inside the fitting when you try to twist them out. Get a good game plan going and rip all the old stuff out.

 

[oh'mike]

Plumber 666 is absolutely right---start right at the water main---you may need a new water meter union.


However there is one possibility that should be considered temporary--

There are large compression fittings available that allow you to cut the old pipe off instead of attempting to unscrew it.

You would use a 1 inch fitting on 3/4" galvanized---then add 1" copper to the output side of the fitting---then reduce the 1" copper down to 3/4".

These fitting are available at any plumbing supply house or The Depot.
Cost about $20---

 

[Just Bill]

Black iron is generally used for gas and heating, not for potable water. Galvanized steel was used for potable water. As suggested above, replace it all!!

 

[cbzdel]

My whole house has been updated to copper pipes already.. Its is steel pipe from water meter until it gets to the crawl space, then after about 4' of it being in the crawl space it is all new copper.

right after it it enters the crawl space it his a "T"' and one side goes to the new copper and the other side goes to an old leaky spigot, which is what I wan to replace with a modern one.

here is what I am trying to do:

existing:

what I would like to do:

Maybe there is a better way to do this?

Replacing the pipe from the water meter would be a PAIN IN THE you know what haha.. I would have to tunnel under a 6' tall retaining wall, that is holding up my front yard.

 

[oh'mike]

I take it that your water meter is out side----you will have to wait for a plumber with a good idea to chime in--I'm all out.---Mike--

 

[WDR]

If I was left in this situation I would try to dig the pipe up outside the foundation and connect to it outside. Everyone else is right about it failing and leaking. The pipe outside will at some point start leaking and will need to be replaced anyway. How far is your meeter from your house. If it is some thing like 20 feet you might be able to use a garden hose and jet a hole out to the meeter for a pipe. I have gotten 20 feet of 1-1/2 pvc thru clay by pushing it with a garden inside it with a jet nozzle. If you have a finnished basment this might not be a good idea.

 

[TheEplumber]

In regards to repairing the pipe in the crawl I would cut the vertical galv. pipe at least 6" above the tee. Then using a good pipe wrench(with a back up on the tee) attempt to spin out the pipe. If it comes out, put a plug in its place. Now move to the existing copper and cut in a new copper tee to feed your new hose bib. You may need to apply heat to the galv tee to help get the pipe loose. The heat should expand the tee just enough, but you will need to drain the water first.
The galv pipe outside should be replaced. We bury our line 5' deep so this is not always a DIY project because heavy equip. is needed. Sometimes we can pull a new copper or poly line though the ground by attaching it to the existing pipe while at the same time pulling the old line out. This method eliminates a lot of digging.

 

[cbzdel]

replacing the whole pipe sounds like a big job, well to me.. I think I may have to bring in the power of a pro! Not sure how deep the water line is here, I know where it enters the crawl space its only about 18" under ground.