Help - Underground Gas Line Issue.

Jun 04, 2004 5 Replies

I had a plumber install a underground gas line for an outdoor fireplace. He installed a shut-off by the house, and used a properly coated gas pipe. What concerns me is the galvanized fittings were not treated in any way.



My mason is ready to pour a slab over the line, and now I'm freaking out about the fittings rusting and leaking. The plumber turned out to be a flake, and is nowhere to be found.



Should I have the line dug up, and have the fittings treated?



Will they last if left untreated?



How do I treat the fittings?



What is there danger of an eventual leak?


The galv fittings will probably last a long, long time; the weak point is the threads on the pipe right where they enter the fitting. Call your gas co. and ask what materials (plastic pipe) are commonly used today in your locality for underground work.

Jim

You may want to check with your local gas company to see what they recommend. My understanding is that galvanized and copper are not to be used because the zinc/copper has a chemical reaction causing corrosion with the chemical added to natural gas to give it the odor so that you can smell it. In the case of copper it then fails, while galvanized tends to have the corroded zinc flake off and clog jets.

At minimum, do not pour concrete in contact with the gas pipe. Leave a space between the piping and the concrete. If possible leave enough room to be able to remove and replace the pipe and fittings. If you don't there is no way to do any repairs without breaking up the concrete and possibly anything built on top of it.

No matter what materials you use, the concrete should NOT touch the piping, there should be a plastic tape wrap or other coating on the pipe and fittings to protect them from the alkaline materials in the concrete.

ALL the pipe, fittings included, should have been sealed over. Better yet you should have used polyethelene pipe rated fror underground gas. Another option would have been SST. You have a mess on your hands, get it fixed before the concrete comes! Greg

Thank for your help everybody.

I decided digging dirt up now would be easier than digging up concrete later.

I wrapped all the joints with 20mil. pipe wrap tape.

The line is itself is about 12-18" below grade - so no worries there.

Thanks again,

Greg

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required