To light the pilot on a Williams gas furnace, turn the valve to off, and wait at least 3 minutes for any gas to dissipate. Locate the pilot inside the furnace, light a match, place it near the pilot, and turn the valve to pilot. Press the dial for lighting.
Before starting the pilot lighting process, the user should set the thermostat to the lowest setting. Once he has lit the pilot and it is burning steady, he should turn the control knob from pilot to on and adjust the thermostat to the desired temperature. If the room temperature is below the thermostat setting, the pilot ignites the burner.
If the pilot does not stay lit after following the lighting procedure, the thermocouple sometimes requires replacing. This metal tube has a bulb located in the flame of the pilot. It is a safety valve, which shuts off the gas if the pilot goes out. A malfunctioning thermocouple shuts off the gas, even though the pilot is operating correctly.
Gas furnaces require regular maintenance to ensure they continue to operate efficiently. A professional heating and air conditioning technician should check the furnace every two years. This routine maintenance ensures the unit operates efficiently and reduces the chances of the pilot light going out due to a malfunction.