In an adjustable head burner, what component must be adjusted to change the air ratio?

In an adjustable head burner, adjusting the draw assembly is crucial for changing the air ratio. The air-to-fuel ratio is vital for achieving optimal combustion efficiency and minimizing emissions. The draw assembly directs the airflow into the burner, ensuring the correct mixing of air with the fuel before it enters the combustion chamber. By modifying the draw assembly, technicians can increase or decrease the amount of air that mixes with the fuel.

The fuel nozzle primarily controls the amount of fuel injected into the combustion process, while the combustion chamber is where the fuel and air mix and burn. The blower motor is responsible for providing the necessary airflow but does not directly adjust the air ratio; instead, it generates a consistent airflow based on its speed settings. Hence, adjusting the draw assembly is the most effective way to influence the air ratio in an adjustable head burner.