What is the function of a draft fan in a boiler?

The function of a draft fan in a boiler is crucial for maintaining efficient combustion and ensuring safety within the system. It helps control the flow of air necessary for the combustion process, adjusting the amount of air entering the boiler to ensure that the fuel burns efficiently. By regulating this airflow, the draft fan allows for optimal combustion conditions, which can improve fuel efficiency and reduce emissions.

Additionally, the draft fan is responsible for the removal of flue gases, which are byproducts of combustion. This removal is essential to maintain a safe operating environment by preventing the buildup of harmful gases within the boiler and in the surrounding areas. By ensuring proper exhaust of these gases, the draft fan plays a key role in keeping the system safe and efficient.

Other options do not align with the function of the draft fan. Increasing the pressure of steam is managed by other components such as boilers or pressure vessels, while circulating water in the boiler system is focused on the water circulation pumps. Similarly, providing cooling is not a function associated with the draft fan; rather, it is designed for air management and flue gas removal.