Clean the burner if the boiler has trouble starting or sustaining a flame. Remove the front panel jacket. Disconnect the pilot tubing from the gas valve. Disconnect the sensor cable and ground wire from the ignition module. Disconnect the Flame Rollout Switch wires. Remove the burner access panel. Grasp the burner by the elongated "throat" and lift slightly to clear the orifice. Withdraw the burner from the combustion chamber. Use a soft brush to clean the top of the burner. Use a narrow attachment to vacuum the burner. Vacuum the tip of the Pilot Burner. Clean the firebox by vacuuming it. Reinstall the burner and all components in reverse order.
Ensure that no objects are obstructing the airflow and ventilation surrounding the boiler. Poor ventilation can hinder the necessary oxygen from reaching the flame. An impeded airflow might snuff the pilot light.
Inspect the pilot tubing from the gas valve if the pilot flame fails to light or ignites intermittently. If the tubing is worn or damaged, replace the tubing immediately. Confirm that the tubing firmly connects to the gas valve.