Posted by: Jeff Ahbe
Gas piping is generally iron or steel with malleable iron pipe fitting. When connected, join compound is applied to the male threads. It is important to verify the compound is approved for all types of gas before you use it when installing gas pipes. You should never use aluminum tubing, sweated connections or cast iron fittings on a main gas line.
When installing a new gas line, you should use pipe fittings on all turns. Do not bend or lap weld your pipe as it can pinch or weaken the line. Support your pipe with bands, straps, hangers or pipe hooks and never let two pipes touch each other. Your piping should also be protected from freezing and accumulating condensation. Pitch all horizontal pipe so that it will lean towards the meter without the occurrence of sags. If you ever find pipe fittings that are defective you should replace them right away, never try and repair them!
Gas leaks on pipes and pipe fittings can be found by spreading a soap solution over the surface. Never try to locate a gas leak with a flame for obvious reasons – extremely hazardous!
Tips for Installing Pilot Shutoff Valve
- Install the pilot valve on the inlet side of the main manual gas shutoff valve.
- Install a ground join union on the gas line between the burner air duct box and the tee fitting in the riser
- Install the main manual gas shutoff valve on the riser at least 4 ft above the floor level.
- Install a tee fitting at the bottom of the riser to catch any foreign matter in your pipe. The bottom of the tee fitting should be plugged or capped.
- Install a pilot supply line between the pilot valve and a point located on the upper right side of the air duct bo on the gas burner. This line should run parallel to your riser.
Make sure you understand the ins and outs of gas piping before you try and install your own. If you do not, consult a local Heating and air conditioning contractor or plumber.
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