From time to time the pilot light on your gas boiler may go out for a variety of reasons, from high-pressure winds blowing down the exhaust vent to flooding in your basement. Modern pilot lights are designed with safety valves and, in some cases, electric ignition, so it is a relatively safe home repair. You may want to call your service company to determine if restarting the pilot on your own will void its warranty.
Turn the thermostat on the gas boiler to the lowest position, depending on the model. Turn off all electrical power to the gas boiler and smell for gas lingering in the air. Allow gas to dissipate.
Search toward the bottom of the machine for a diagram or label indicating the pilot light's location. Remove the snap-on metal plate covering the pilot light. On some models you may have to remove several retaining screws to access the pilot, using a screwdriver.
Push the gas control knob in and turn it clockwise to the "off" position.
Press down the gas control knob on the pilot valve, located on the left side of the burner, and turn it to the "pilot" position. Hold the knob in the down position to release gas from the pilot.
Strike your match or light your grill lighter and hold the flame up to the pilot burner. Once the pilot has lit, continue to hold the knob down for about one minute. When you release, the pilot should remain lit. If not, repeat this process until the pilot stays lit.
Turn the gas control knob to the "On" position.
Press the gas control knob in and turn clockwise to the "off" position.
Press in the gas control knob and turn it to the "pilot position." Press the gas control knob in and then press the electric ignition button immediately after. You should hear a loud click, after which the pilot should light.
Hold down the gas control knob for one minute. Release the knob and turn it to the "On" position.
If you smell gas in your home or around the boiler, do not attempt to relight the pilot. Do not touch any electrical appliances or turn on any electrical switches. Leave your house immediately and use a neighbour's phone to call your gas supplier. Do not attempt to light a boiler that is or has been submerged in water due to flooding. Call your service professional immediately. Always consult your manual before attempting to relight a pilot to determine the correct method for your model.