Gas Fitter Practice Test

The air supply duct should be positioned within 12 inches above the burner to ensure effective combustion and proper airflow. This distance allows for sufficient intake of combustion air while minimizing the risk of interference with the burner’s operation. Importantly, maintaining this distance helps prevent overheating of the ductwork and ensures that air enters the combustion zone at the optimal temperature and volume. Adequate air supply is crucial for achieving efficient combustion, which in turn leads to better performance and reduced emissions.

Distances greater than 12 inches could impede necessary airflow dynamics, while being closer than 12 inches might lead to potential safety issues related to heat and combustion gases. Thus, the specified position is designed to promote safety and efficiency in gas appliance operation.