What is air mixed with natural gas in the burner called?

The correct term for air mixed with natural gas in the burner is referred to as primary air. In the context of gas burners, primary air is the air that is mixed with the fuel (natural gas, in this case) before it enters the combustion zone. This mixture is crucial for the efficiency and effectiveness of the combustion process. The proper mix of primary air and fuel leads to optimal combustion, ensuring that the gas burns completely and efficiently, minimizing emissions and maximizing heat output.

Understanding the role of primary air is fundamental for technicians working with gas furnaces because any variation in the air-to-fuel ratio can result in incomplete combustion, leading to potential safety hazards as well as a drop in system performance.