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howardssmith
Jan 24, 2007, 08:39 AM
I want to add a branch line to an existing gas line for a new kitchen stove. The problem is there is no way to disassemble the existing gas line. No unions. The line is located in the attic space above the garage.

Can I safely cut the existing gas line to remove a section of pipe? It will be filled with natural gas but the gas will be shut off.

myoldhouse
Jan 28, 2007, 07:59 PM
What would you use, a brass saw? My advice would be to find the nearest gas-certified plumber in your area to do your tap. Gas lines must be properly sized for the appliance they serve, and any leaking that may occur if things aren't buttoned up right would be a disaster. This is one area I wouldn't tackle on a DIY level-I hope you don't either!//dave

labman
Jan 28, 2007, 08:32 PM
There should be a union at the gas meter and at the stove. Can you work from either? If not, not only shut the gas off, but let something run until all the gas runs out. A pipe cutter would be better than a hacksaw. Make sure you have good threads on all your new pipe. Most places that sell pipe will cut and thread it for you. Teflon tape is good, but I like the Loc-Tite Pipe-X I find at the auto parts store better.

skiberger
Jan 28, 2007, 08:52 PM
Like MOH said get a plumber.
Running black pipe in concealed areas is against code. Have the plumber run a length of Gas-Tite or Ward Flex gas line (yellow cover flexible gas line) Then you only will have 2 joints. One at the gas meter union and the second at the appliance. This is the safest and code required gas line to use.

letmetellu
Jan 28, 2007, 10:14 PM
For many years I have sawed gas lines with an electric jab saw. Rent some threaders and re-thread the pipes you cut and then put a tee and a union and a nipple between them.

iamgrowler
Jan 29, 2007, 08:29 PM
Running black pipe in concealed areas is against code.

Nonsense.

Concealing black pipe isn't against code in either the IPC, UPC or SPC.

What *IS* disallowed in all three, though, is the concealment of ground joint unions.

iamgrowler
Jan 29, 2007, 08:39 PM
I want to add a branch line to an existing gas line for a new kitchen stove. The problem is there is no way to disassemble the existing gas line. No unions. The line is located in the attic space above the garage.

Can I safely cut the existing gas line to remove a section of pipe? It will be filled with natural gas but the gas will be shut off.

Your best bet would be to back the pipe out from the meter union to the first or second 90 in the attic space, where you would replace the 90 with a tee and then take off from the tee from there.

The advice about shutting the meter off and flaming the residual gas off at the nearest flammable source was spot-on.

If this isn't an option -- Then turn the meter off, remove the union from the meter, uncap a drip-leg from downstream and use an air compressor to purge the line -- Most domestic NG is low pressure, and being heavier than air, it will remain in the pipe, even when not under pressure.

labman
Jan 29, 2007, 09:14 PM
Natural gas is lighter than air. It has even been used in balloons. But it still wants to stay in the pipe.

iamgrowler
Jan 29, 2007, 09:19 PM
Natural gas is lighter than air. It has even been used in balloons. But it still wants to stay in the pipe.

>smacks forehead<

*DOH*

You're right, of course.