Gas appliances need pilot lights to operate correctly. The pilot tube supplies a small amount of gas to the pilot orifice, creating a small flame to heat the tip of the thermocouple. If the orifice is clogged, the flame can't burn and the thermocouple can't send a message to the gas supply valve. If no message is received by the gas supply valve, the gas supply valve shuts off the gas supply to your appliance. Clean your gas pilot tube to keep your appliance burning.
Locate the shut-off valve on the gas line and turn it clockwise to stop the flow of gas to your appliance.
Remove the thermocouple and the pilot tube from the gas supply valve using an adjustable wrench. Follow the pilot tube to locate the pilot assembly. The pilot assembly holds both the thermocouple and the pilot orifice. The assembly is held to your appliance by screws. Remove the screws to pull the assembly from your appliance.
Turn the pilot tube counterclockwise to disconnect the pilot tube from the pilot orifice. Use fine-grit sandpaper to clean the tip of the orifice, removing any oxidation. Push a small, stiff wire through the opening on the pilot to dislodge any clogs. Blow compressed air through the pilot orifice to remove any loose materials from the orifice.
Reattach the pilot tube to the pilot orifice and reattach the pilot assembly to your appliance. Reconnect the pilot tube and the thermocouple to the gas supply valve and turn on your gas supply.
Relight your appliance pilot if necessary and follow the directions printed on the exterior of your appliance for specific lighting instructions.