Learn About Gas System Basics
When you want to add or relocate a gas appliance, keep in mind a few basic requirements. There is no room for error when installing a gas system. Unless you are experienced, it is best to have a professional to make the installation. You must, in any case, have the work inspected before the gas is turned on.
Materials approved for gas supply vary with the area and the type of gas. The most universally accepted indoor materials are a threaded pipe of galvanized steel, and “black pipe” (threaded steel pipe without galvanizing). For outdoors and direct burial, choose “green”, or coated, steel pipe. Heavier grades of copper pipe used for plumbing systems are also permitted in some locations. All of them should have proper name tags on them.
The local plumbing code or a separate gas code will specify pipe size according to cubic foot capacity and the length of pipe between the meter and storage tank and the appliance. All the gas appliances should have a numerical rating in BTUs per hour stamped right on the metal name tags.
Each appliance should have a code-approved shutoff valve with a straight handle to turn off the gas in an emergency. Shutoffs must be rated for your type of gas and must be located in the same room as the appliance.
An appliance is connected to the shutoff valve with either solid pipe or flexible tubing designed for gas. When using solid pipe connectors, add a union fitting that will allow you to disconnect the appliance. If you use a corrugated flexible connector, join it to the shutoff valve with brass flare fittings. Some gas shutoff valves come with a built-in flare fitting for the flexible appliance connector; others require you to thread the flare fitting onto the valve or pipe.
To test extensive runs of new gas lines, cap off all the students, screw on a pressure gauge, and pump up the line with 10 to 20 pounds of air pressure; maintain it for 15 minutes. Falling pressure indicates a leak. To find it, brush soapy water onto the fittings and look for telltale bubbles. Try tightening the connection; disassemble and reconnect as necessary.
You may also use the soap suds technique to test your appliance connections and other small scale alterations you have made to your gas lines.