Adding gas lines for range, dryer, fireplace, and garage heater
Posted by Mark on April 02, 2004 at 20:04:37:

We've recently closed on a house that has a natural gas furnace and hot water heater. We would like to branch off the existing line (or run new line if the current piping won't supply enough volume or whatever) to supply a gas dryer, gas range, gas fireplace conversion (of an existing wood burning fireplace), and a ventless gas garage heater.

I'm well aware that I need to understand all the safety aspects related to working with natural gas. I'm well aware that most folks don't do this themselves. I also don't have very much money, having just closed on the house, and am quite comfortable working with my hands, have done water plumbing before (yes, I know its not the same thing), etc.

Anyway, so on to the questions...

First, what's the proper way to determine the required piping size? Another post had a chart listing the volume a given pipe diameter and length could supply, along with a chart of normal btu/hour, etc. that appliances use. What I didn't see was how to convert the btu/hour into the volume. Can anyone help with that?

Second, it seems like I can either use a left/right nipple/coupler or a union to branch into the existing line (if that pipe size is appropriate). All my connections will be in the basement and exposed. As I understand it, a union would therefore be ok. Correct?

Also... when cutting the existing line, obviously I'll be turning the gas off. Do I also need to purge that line using air or something? Will a regular copper pipe style tubing cutter work on black iron pipe? I guess I could use an abrasive wheel, but I'm _really_ not excited about that as its throwing sparks/heat...

Anything else I should know? Are there any references online with headings like "so you're going to run your gas lines yourself anyway, despite all the recommendations otherwise. Here's how you can do it safely..."?