What ignites the fuel in the ignition system on an oil burner?

In an oil burner ignition system, the fuel is ignited by a high voltage spark, typically around 10,000 volts DC. This high voltage is generated by an ignition transformer and is essential for producing a strong enough spark to ignite the fuel oil as it is atomized and sprayed into the combustion chamber.

The high voltage spark creates a discharge that can jump the gap between the electrodes, igniting the fine mist of oil being introduced into the combustion area. This process is crucial for starting the burner and ensuring a consistent and efficient combustion process, which is vital for the operation of heating systems that use oil.

While other options may involve flames or mechanical processes, they do not effectively initiate the combustion in the way that a high voltage spark does. For instance, a flame from the burner or a pilot light represents a continuous source of ignition rather than the initial ignition method used during startup. Compression from the fuel pump is involved in fuel delivery but does not directly relate to the ignition of the fuel itself.