Spark Generators

A spark generator on a boiler or gas fire is an electronic device to begin combustion on demand.

Decades ago boilers and fires had a pilot light, a constantly burning flame, so that there was always fire ready when a combustible gas or liquid was released for combustion.

However pilot lights waste fuel, so a spark generator was developed. This is a special type of electrical  transformer which increases a 240 volt electrical current up to about 20,000 volts, enough for a spark to jump across an air gap on a spark electrode and ignite fuel on demand.

This is known as a step up transformer as it increase the voltage from the primary input circuit to the secondary output circuit.

If you are familiar with an internal combustion engine, the spark electrode is the equivalent of a spark plug, and a spark generator is the equivalent of an ignition coil.