Most contemporary gas ranges have electronic ignition devices to start the flame on the burners and in the oven when you turn on the controls. On older models, however, as well as some contemporary ones, you might find a standing pilot instead. This is a small flame that must be constantly burning for the appliance to work. It isn't unusual for the pilot to go out, and it's easy to relight. You should consult the manual for your model for details about where the pilot is located, but most of the time, you'll find a pair of pilots for the burners on the stovetop underneath a cover and one for the oven underneath the floor.
Why Did the Pilot Go Out?
A gust of wind is all it takes for a pilot to go out, but sometimes the problem, especially in the oven, is a blocked pilot tube. Another common problem is a worn flame sensor, sometimes called a thermocouple, which controls the oven pilot. This component consists of a metallic probe attached to a copper tube which is in turn attached to the gas valve. Its job is to keep the valve open when the pilot is on so that gas flows and the pilot stays on. If you can't get the oven pilot to stay lit by following the recommended procedure for lighting it, you should call an appliance pro to replace the thermocouple.
Start with the Burners
Before lighting the pilot in the oven, it's important to make sure the burners are working, because you'll need to turn them on before you light the oven pilot. If nothing happens when turn on one of the burners, you may have to relight the pilot for that burner. There are usually two pilots—one for the burners on the left and one for the burners on the right.
To relight the burner pilots, remove the burner caps, if there are any, grasp the front of the stovetop and lift it up to give yourself access to the gas pipes underneath. If the stovetop doesn't have a built-in prop to keep it in position, hold it up yourself or have a helper do it.
Note the pilot opening in the pipe midway between each set of burners. Light a long-barreled lighter and hold the flame inside the opening until you see a small blue flame begin to burn. Remove the lighter and make sure the flame keeps burning. If it goes out, you may have to clan the pilot opening with a needle. Once both flames are burning steadily, you can replace the stovetop and the burner caps.
Light the Oven Pilot
In most ovens, the pilot is in the rear of the oven compartment. You might be able to access it by removing the bottom drawer, but in many cases, you have to remove the oven door and floor to get to it. To remove the oven door, open it, grasp both sides and lift it off its hinges (be careful, it's heavy!). After setting it in a safe place, remove the screws holding the floor and slide it out to expose the gas pipes underneath.
The pilot orifice is at the end of a small tube just above the oven burners. Before you light it, turn on the two back burners on the stove to bleed air from the gas line. Push in the oven control while you hold a lighter in front of the pilot orifice. This may require the help of another person. Remove the lighter when the small, blue pilot flame starts burning, but keep the oven control depressed. Release the control after 30 to 60 seconds and verify that the pilot stays on. Turn off the stove burners, replace the oven floor and door and the oven is ready to use.