I am planning on adding a natural gas stove in our kitchen, replacing an electric one. Right under the stove in the basement below, there is currently an interior gas line run to the water heater. It is a copper run (1/2" - but not sure yet if that is 1/2" ID or OD) of 40-50' from the other utility room on the other side of the house where the furnace and main gas line entry point is. Originally, I was planning to just use that supply, and T it out to go up to the stove and down to the water heater. I would use black iron to do the short connections, because I have done that before. I've also done a lot of copper for water, but not for gas.

Q1) If the copper run is 1/2" ID, I suspect that will not provide enough supply to run both stove and W.H. simultaneously. At least that's what the guy at the local hardware shop said.

If I replace the copper run, I would prefer to use black iron, since I am not super happy about rolling out a whole new bigger copper line - working conditions are tight and I really don't want to kink it and have to start over. Q2) My main question is about the quantity of junctions on a black iron run, and using couplers in-line? It is just a run up to ceiling, across about 25', right turn and then about 25' in the next direction - but those lengths will likely require in-line junctions, since I don't know where to get black iron longer than 20'.

Open to constructive thoughts on this project. Thanks!

 

Welcome to the forums.

I am not the plumbing pro but I can tell you 1/2" copper is too small for your needs there.

For home applications.... the iron pipe will usually be 3/4"x10' and then you use 3/4" threaded couplers.

So you are talking about a run of approx 55 or so feet ?

 

I'm not an expert either. I install new ranges to existing pipe only, and move/relocate pipe as needed.
That said you should run a new 3/4" line all the way back to the meter.
If there is a 1" line in the furnace room you could probably tap off that with black iron, but can't confirm.

On my jobs where a new line was installed, this is what the inspector wanted to see:
- 3/4" line direct from meter or a manifold
- 3/4" pipe stub out behind range with a 3/4" valve or 3/4" pipe reduced to 1/2" valve.

To give you an idea a 1/2" x 48" gas flex hose will deliver about 106,000 BTU.

 

Copper foe natural gas is a code violation in many areas including mine because of the potential fror corrosion from the level of sulfur in some natural gas sources.

This forum recommends you do not run your own gas line. It is too dangerous if you make a mistake. Call a plumber.

 

First things first, it is black STEEL, not iron, pipe. Steel pipe of schedule 40 wall thickness is manufactured in lengths of 21 feet and with threaded ends. Most steel pipe readily available to consumers in the US is imported from Asia. The pipe, and especially the fittings, from at least one Asian country are infamous for poor quality control. Because price is the controlling factor it is pipe and fittings from this country that are common at big box mega-mart homecenters. Also, the homecenters usually do NOT change the dies on their threading machines often enough resulting in poorly cut threads when they make custom lengths.

The material of choice these days for natural gas piping is CSST, Corrugated Stainless Steel Tubing. Some of the homecenters will carry this material in different diameters and lengths. It is quite flexible, more so than soft-temper copper so installation is fairly easy. Your particular jurisdiction may not have approved CSST yet so even if the big box has it there is a possibility you can't use it. Check with the inspection office before buying.

 

In Northern Virginia, most natural gas runs inside homes are/were done in black iron pipe (which in fact is steel painted black). However some runs are done in copper, most commonly when the run has to snake past obstacles or be fished through walls. When done in copper, it is typically done in soft copper with flared fittings.

However, we also have a number of homes that were converted from all-electric service to supplementing that service with two-pound (2PSIG) Natural Gas for furnaces, water heaters, and/or cooking. Our code authorities and gas companies required special training and certification for installers doing 2PSIG installations or conversions. The advantage of 2PSIG were that it allowed smaller piping/tubing to be run over greater distances than standard pressure -- significant reduction in installation cost and reduced disruption of existing finishes as the piping can be fished. It was also pushed for supplying pool heaters, as the runs are often fairly long. Key points I retained from 2PSIG training: 1) separate runs for each appliance, sized for that appliances btu requirements; 2) use a step down regulator for each appliance to bring it down to 8-12" WC; 3) use 45-degree flare fittings. Bottom line, if you have 2PSIG, then you will need to deal with it differently than if it is regular service.