What is one key function of a draft fan in a boiler system?

The key function of a draft fan in a boiler system is to improve air flow. Draft fans are utilized to ensure that there is an adequate supply of air for the combustion process within the boiler. By enhancing the flow of air, these fans help maintain the necessary oxygen levels required for efficient burning of fuel. This improved airflow not only promotes more complete combustion, which increases the system’s efficiency, but also facilitates the removal of flue gases from the combustion area, helping to maintain a safe and effective operating environment.

In boiler operations, sufficient air flow provided by the draft fan helps to stabilize the combustion process, preventing issues such as soot formation or incomplete combustion that can lead to higher emissions and decreased performance. Proper air flow also contributes to the overall safety of the boiler by ensuring that combustion gases are effectively expelled from the system.

The other options relate to functions that are not directly managed by a draft fan. For instance, regulating water flow is associated with water system components, vacuum pressure creation is typically handled by different types of fans or blowers, and controlling exhaust temperature involves heat exchangers or controls within the boiler rather than the draft fan itself.