An intermittent pilot system uses which method to ignite?

An intermittent pilot system ignites using a spark or hot surface igniter to light the pilot. This method is efficient and enhances safety by only activating the pilot light when the main burner is needed. In an intermittent pilot system, when there is a call for heat, the igniter generates a spark or heats up a surface until it reaches a temperature sufficient to ignite the gas at the pilot outlet.

This approach is superior because it eliminates the need for a continuously burning pilot flame, which can waste energy and create safety concerns associated with an always-on flame. The use of spark or hot surface igniters also reduces gas emissions compared to traditional systems.

Alternatives like using a candle or a match would not be practical or safe in a modern heating system, as they pose risks of flame control and reliability. A fan to blow the flame is not applicable in this context, as the ignition process relies on direct application of an ignition source to the gas, not on the presence of airflow to sustain or initiate combustion.