What is a significant consequence of poor airflow on boiler efficiency?

Poor airflow significantly impacts boiler efficiency, primarily contributing to incomplete combustion. When there is insufficient airflow, the fuel does not receive enough oxygen, which is essential for the combustion process. This incomplete combustion not only reduces the amount of energy generated (heat output) from the fuel but also leads to the production of unburned hydrocarbons and other pollutants that increase emissions.

Emissions such as carbon monoxide and particulate matter can result from this lack of proper combustion, which could also potentially lead to environmental compliance issues. Additionally, inefficient combustion affects boiler performance, resulting in potential safety concerns and increased operational costs due to the need for more frequent maintenance and repairs.

In this context, the other choices do not accurately represent the consequences of poor airflow. Increased heat output cannot occur without adequate combustion, while decreased fuel consumption is unlikely since incomplete combustion typically results in requiring more fuel to achieve the desired heat output. Lastly, lower operational costs are contrary to the reality that inefficiencies often lead to higher costs associated with energy use, maintenance, and emissions control.