What is the primary function of a pilot flame in a gas furnace?

The primary function of a pilot flame in a gas furnace is to ignite the main burners. In a typical gas heating system, the pilot flame serves as a small, steady flame that burns continuously. When the thermostat calls for heat, the gas valve opens, allowing gas to flow to the main burners. The presence of the pilot flame is crucial as it provides the necessary ignition source for this gas. Once the main burners are activated, the pilot flame ensures that the gas burns safely and efficiently, contributing to the overall heating process.

This function is essential for the safe and effective operation of the furnace, as it prevents the buildup of unburned gas, which can be hazardous. The consistent presence of the pilot flame allows for immediate ignition of the furnace when the heating demand arises, ensuring that the system can respond dynamically to temperature changes in the environment.