Given steel and copper are dissimilar metals, is any special connector required to connect them as an underground supply line to sprinklers.

Assuming that by steel you mean galvanized iron pipe with threaded end, just use copper female adapter and start soldering.

I disagree with Harold... If connected the way he suggests, you will create electrolysis. It is "Plumbing 101"...

You have to use di-electric fitting. They sell unions that have Female thread on one side (to gal pipe) and sweat on the other side (to copper ). The union can be either aluminum with plastic washer or brass/copper combination.

Also you could use brass coupling. Brass acts as neutralizing fitting. You screw coupling onto gal pipe and use male thread copper fitting on the other end. Then, continue with copper...

PS: Harrold, wake up...

Hi all:

I don't know if I would even recommend connecting galvi. or steel to copper underground... dielectric union or not!

As far as I know... you can't just solder copper pipes underground..?

In this case, with the limited info. Provided, I would suggest that you run copper underground as one piece... TYPE K copper and have NO joints underground..? Once above the ground you can transition over to the steel or galvi. Using a dielectric union... ;) If you must have copper to copper joint underground it should be brazed or you can use a ford fitting or similar union. I would talk to a local plumbing supply store (see the guys at the counter)... see what they have in stock for this case.

Let us know more about the application... steel or galvi? What size pipes are we talking about? How about distances you are running this? Anything else you think we should know?

Thanks...

MARK

Mark, type "L" is approved U/G grade for copper. "K" is overkill ( my opinion:-D ) You cannot solder copper under concrete SLAB but it is OK to solder under soil cover. That's how most of our water main-lines are installed. At least in my area of operation... but I realize Code may say otherwise on the East Coast...

You know it says otherwise here Milo.. :p

TYPE K copper for all underground here...PERIOD!! No soldering at all... ;) Just like you said... different in each state!

But thanks for pointing out what your area does... great info!

Hope that Ohjoejoe returns and lets us know more!

Mark, just for my info: what do you guys do if you have 100' of water main to run ?

We don't... always seems to be an alternative to that. We almost always find a way to run minimum copper piping underground and then stub up and run pipes in chaseways.

Underground copper is only to get the main water supply into the building from ductile iron main supplies or between areas... then we pipe all copper above ground!

As stated, however, if we do have to connect between pipes... such as in the case of repair work, we need to braze the coupling or use a FLARE or FORD type fitting.



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I don't want to step on any body toe, would like to add this to your comments that's all.

Do NOT solder lines for in the ground use. Any fittings should be ford fittings which are designed for underground applications. You are better off running black plastic well pipe. It is cheaper, faster and designed for it. If you choose copper then you will need to use K copper only with the combination of ford fittings. Either way the need to be below frost line and should be covered in stone screening for protection. Hope that helps, Thanks.

John

FYI: Mark, now I am learning you can actually buy coils of 60', 100' and 200' of type "L" and "K" copper.

John: As always, thanks for your output.

Thanks for the update Milo...

I've used the 60' and 100', but didn't know about the 200'... Wonder what that baby would cost (and weigh) in 1.5" or 2"... huh? ;)

MARK