What is the function of interrupted duty ignition in a gas furnace?

The function of interrupted duty ignition in a gas furnace is indeed related to the operation of the gas valve in response to the ignitor. In this context, when the ignitor is energized, it heats up to ignite the gas that is released from the gas valve. The gas valve remains closed until the ignitor is heated to a sufficient temperature to ensure a safe and effective ignition of the gas.

This method of ignition enhances safety and efficiency by preventing gas from flowing continuously when there is no ignition source present. It also allows for a controlled ignition process, where the gas valve opens only when the conditions are right for ignition to occur. As the thermostat satisfies the heating demand, the ignitor and gas valve will respond accordingly, ensuring that the system operates smoothly and safely.

In summary, the correct choice highlights the crucial relationship between the ignitor and the gas valve in creating a safe ignition process, which is foundational to the operation of a gas furnace with interrupted duty ignition.