Working on whole house remodel. Finished plumbing some time ago. Attached garage is my workshop - but its cold. Decided to add a Hot Dawg natural gas unit for heat. Need to back out (black pipe) gas line (kitchen and water heater to add "T" (local CA reg). I can access all elbows/pipe by removing finished drywall. Question: should I replace all elbows? My concern is re-fitting tappered threads and having to open walls to access. If answer is "no", all work would be in accessable attic. I know I could "try and see" with standard pressure test - just looking for "proper" approach.

You have to "remove drywall" to remove the elbows so that should not be a consideration. You probably want to replace any fittings because when you screw the old ones on, they will be snug when they reach the point where they were originally, but you may have to turn them past that point to be tight, and they may "stop" before you reach the orientation you need.

Would like to have a clearer explination of concerns.
I cannot imagine replacing a bunch of gas plumbing elbows for the sake of replacing elbows per se
Try this tap into gas line with Tee run gas line to workshop, cap existing gas lines before shut off valves pressurize with air for leaks then install shut offs and flex spray with solution looking for exposed leaks and finish up
in other words I would think tiing into gas line with a tee would only require " stabilizing' one existing fitting
maybe I missed something ?

I wouldn't be afraid to use old fittings.

dope, then tape and tighten. I wouldn't sleep well unless I tested any gas system I installed with air test.

He is saying that instead of using a union buried in a inaccessible location, he would disassemble the gas line, starting at the appliance, until he reached the spot where tee in place of an elbow would be needed, then reassemble the gas system.

? left-right nipple + coupling ?


oops, that pesky 'best practice thingy again

Quote

Left/Right & Di-Electric Fittings

If you've been searching for those elusive left/right threaded black iron fittings, you've come to the right place.

These have standard right-hand threads on one side & reverse (left-hand) threads on the other. These are generally used for gas piping, when unions are not allowed.

[www.plumbingsupply.com]

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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638



Edited 1 times.

HJ - Thank you, you grasp my question. In my California locale I'm not permitted to add union or left-right-left - so backing out is only option I'm aware of to get back to 3/4" supply. I think I'm going to go ahead and cut out drywall to get to access to involved elbows. Drywall (two cutouts) are concealed behind kitchen range and water heater closet - and I'm confident I can refinish to match surround surface. As the only other gas device connected at this point in the remodel is the furnace, my intent is to close the ball valve there and re-pressure test the entire line (other stub outs were previously caped / tested).



Edited 1 times.

Thanks
HJ for hepling with my explaniation